Cells

Waxes

A _________ is a lipid that is extremely hydrophobic and are rarely found in the cell membranes of animals. In plant cell membranes, they provide stability and rigidity to nonpolar sections of the phospholipid bilayer.

Amphipatic

A _____________ molecule is a molecule that has both a polar region and a nonpolar region. A phospholipid is a _____________ molecule

Glycoprotein coat

A ______________ is a protective coat formed by glycoproteins that is used for cellular interactions with water

Phospholipid

A ______________ is the main molecule that makes up the cell membrane that is comprised of a phosphate molecule, a glycerol molecule, and two fatty acid molecules. It can also serve as second messengers in signal transduction.

Vesicle

A __________________ is a bubble-like structure that is formed from the phospholipid bilayer that is used to transport molecules across the cell membrane.

Bivalent chromosome

A _________________________ chromosome is a chromosome that contains 2 sister chromatids.

Monovalent chromosome

A ___________________________ chromosome is a chromosome that contains only one chromatid.

G-protein

A ____________________________ is called this because it binds to molecules that include the nucleotide guanine.

Answer: A. A bacterial cell that does not rapidly cause a phenotypic change in the rest of the colony is likely not F+, meaning that this cell is not able to form a sex pilus and conjugate, making (A) correct. The expression of new phenotypic characteristics indicate that this bacterium may have acquired genetic material from the environment through transformation, (B), or transduction (which occurs via bacteriophage infection), (C) and (D).

A bacterial cell is noted to be resistant to penicilin. The bacterium is transferred to a colony that lacks the fertility factor, and the rest of the colony does not become resistant to penicilin. However, the penicilin-resistant cell has also started to exhibit other phenotypic characteristics, including secretion of novel protein. Which of the following methods of bacterial recombination is not likely to account for this change? A. Conjugation B. Transformation C. Transduction D. Infection with a bacteriophage

Answer: D. Cells that are able to divide indefinitely with no senescence are not exhibiting normal cell behavior. Normally, somatic cells divide a limited number of times until the telomeres become too short to be effective protectors of genomic material. When this occurs, the cell stops dividing. However, in this case, the cells have continued to divide indefinitely. It is likely that the enzyme telomerase has been activated, which allows for synthesis of telomeres to counteract shortening during DNA replication.

A cancer cell is removed from a patient and cultured. The cells in this culture seem to be able to divide indefinitely with no cellular senescence. Which protein is likely activated in these cells that accounts for this characteristic? A. Epidermal growth factor B. Sonic hedgehog C. Transforming growth factor beta D. Telomerase

Answer: C. The question stem states that a cell releases a substance that diffuses through the environment and causes differentiation of a nearby cell. Because the cell is acting on a nearby cell and the molecule spreads by diffusion, this is an example of paracrine signalling. Autocrine signalling (A) occurs when a molecule secreted by a cell acts on the same cell. Juxtacrine signalling (B) occurs between adjacent cells, but the signal does not spread by diffusion. In endocrine signaling (D) a molecule is secreted that travels via the bloodstream to a distant target.

A cell releases a substance that diffuses through the environment, resulting in differentiation of a nearby cell. This is an example of what type of cell-cell communication? A. Autocrine B. Juxtacrine C. Paracrine D. Endocrine

Answer: C. During development, programmed cell death occurs in multiple locations in order to ensure development of the correct adult structures. One of the places in which this occurs is between the fingers and toes; another is the digestive tract, where a central lumen is formed. If apoptosis does not occur correctly in the digestive tract, an imperforate anus could result. Failure of determination or differentiation would result in the absence of anorectal structures altogether, eliminating (A) and (B). Failure of neuralation would lead to the absence of a nervous system and would not be compatible with life, eliminating (D).

A child is born with an imperforate anus, in which the anal canal fails to form correctly and the rectum is not connected to the outside world. This pathology is most likely accounted for by failure of: A. Cell differentiation B. Cell determination C. Apoptosis D. Neurulation

Peroxisomes are dependent on hydrogen peroxide to break down long chain fatty acids, so the enzyme deficiency that results in the inability to form hydrogen peroxide would result in the inability to digest long chain fatty acids. Fatty acids would build up in the peroxisome until they displaced cellular contents, ultimately resulting in cell death.

A child is diagnosed with an enzyme deficiency that prevents the production of hydrogen peroxide. What would the likely outcome be of such a deficiency?

Answer: D. Membrane receptors must have both an extracellular and intracellular domain; therefore, they are considered transmembrane proteins. In order to initiate a second messenger cascade, they typically display enzymatic activity, although some may act strictly as channels.

A membrane receptor is most likely to be a(n): A. Embedded protein with catalytic activity B. Transmembrane protein with sequestration activity C. Membrane-associated protein with sequestration activity D. Transmembrane protein with catalytic activity

Answer: D. The question stem states that the pregnant woman was given the drug three days before the baby was born. It is important to remember that organogenesis occurs during the first trimester. The last structure to become fully functional is the lungs. Because the organs were already largely formed prior to the administration of the teratogenic drug, it is likely that there was no major effect on the development of most organs as a result if exposure to the teratogen, eliminating (A), (B), and (C). However, because lung tissues are so sensitive and because they mature so late, it is likely that the infant may have some respiratory distress at birth.

A pregnant woman is accidentally given a single dose of teratogenic drug late in the third trimester. The baby is born three days later. Which of the following is the most likely outcome? A. Complete failure of organ development and death of the fetus B. Partial failure of organ development with survival of the fetus C. Serious disfigurement of the fetus D. Respiratory distress at birth, but no long-term effects

Answer: C. This question requires an understanding of osmosis and the action of the sodium-potassium pump. When a cell is placed in a hypertonic solution (a solution having a higher solute concentration than the cell), fluid will diffuse out of the cell and result in cell shrinkage. When a cell is placed in hypotonic solution (a solution having a lower solute concentration than the cell), fluid will diffuse from the solution into the cell, causing the cell to expand and possibly lyse. The sodium-potassium pump moves three sodium ions out of the cell for every two potassium ions it lets into the cell. Therefore, inhibition of the sodium-potassium pump by ouabain will cause a net increase in the sodium concentration inside the cell and water will diffuse in, causing the cell to swell and then lyse.

A researcher treats a solution containing animal cells with ouabain, a poisonous substance that interferes with the sodium-potassium ATPase embedded in the cell membrane, and the cell lyses as a result. Which of the following statements best describes ouabain's effects? A. Treatment with ouabain results in high levels of extracellular calcium B. Treatment with ouabain results in high levels of extracellular potassium and sodium C. Treatment with ouabain increases intracellular concentrations of sodium D. Treatment with ouabain decreases intracellular concentrations of sodium

Answer: C. We are asked to identify the type of transport that would allow a large, polar molecule to cross the membrane without any energy expenditure. This scenario describes facilitated diffusion, which uses a transport protein (or channel) to facilitate the movement of large, polar molecules across the nonpolar, hydrophobic membrane. Facilitated diffusion, like simple diffusion, does not require energy.

A student is trying to determine the type of membrane transport occurring in a cell. She finds that the molecule to be transported is very large and polar, and when transported across the membrane, no energy is required. Which of the following is the most likely mechanism of transport? A. Active transport B. Simple diffusion C. Facilitated diffusion D. Exocytosis

Answer: D. This question stem describes a tumor composed of multiple types of embryonic tissues as well as tissues derived from all three germ cell layers. Because this tumor contains placental tissue, the tumor must have originated from a cell that was able to produce those types of tissues. Cells capable of producing placental tissue as well as ectoderm, mesoderm, and endoderm are, by definition, totipotent.

A tumor is removed from a patient and when investigated by pathologists, appear to contain tissue resembling placenta, hair, thyroid tissue, and cardiac muscle. What was the likely potency of the cells from which this tumor originated? A. Nonpotent B. Multipotent C. Pluripotent D. Totipotent

Answer: A. A virus that requires transport to the nucleus in order to produce viral proteins likely requires use of nuclear RNA polymerase in order to create mRNA that can be translated to protein. Therefore, only DNA viruses need to be transported to the nucleus to produce viral proteins, eliminating everything but (A).

After infection of a cell, a viral particle must transport itself to the nucleus in order to produce viral proteins. What is the likely genomic content of the virus? A. Double-stranded DNA B. Double-stranded RNA C. Positive-sense RNA D. Negative-sense RNA

Intracellular Extracellular

Allosteric sites for ligand-gated ion channels can be ________________________, but this is pretty rare, since ligands won't typically appear from inside the cell. Typically, the allosteric site would be ____________________ for a ligand-gated ion channel.

induced pluripotent stem cells

Any cell, even a highly differentiated cell in the adult body, that has been genetically reprogrammed to mimic the pluripotent behavior of embryonic stem cells

Full-term Full-term is the best option, then early-term and late-term are the second best options, then pre-term and post-term are the least favorable options.

Are offsprings more healthy if they are born pre-term, early-term, full-term, late-term, or post-term?

Yes. Even though post-mitotic cells are unable to divide, meaning they will not be able to reach replicative senescence, they are still able to reach cell senescence if their DNA is at risk of being damaged.

Are post-mitotic cells able to become senescent?

No. Post-mitotic cells are unable to undergo mitosis, meaning they are unable to replicate its DNA for cellular division, meaning that it cannot reach replicative senescence.

Are post-mitotic cells able to reach replicative senescence?

No, because stem cells are able to express telomerase, which allows them to rebuild the bit of telomere that was lost during DNA replication. The telomerase allows the stem cell to divide as many times as needed, meaning that it will never reach its Hayflick limit.

Are stem cells able to reach their Hayflick limit?

Answer: Yes Adaptation to an environment does not have to be present immediately, but can occur over a period of time. Viruses can mutate, meaning they are able to adapt to their environment over time.

Are viruses able to adapt to their environment? Explain your reasoning.

Answer: No Virus uses host cells to create new viruses, meaning each virion is created in its fully formed state and will not grow any further in size or complexity.

Are viruses able to grow? Explain your reasoning.

Answer: No Viruses do not have membrane-bound organelles or cytoplasm like prokaryotes or eukaryotes, thus they are unable to maintain homeostasis.

Are viruses able to maintain homeostasis? Explain your reasoning.

Answer: Yes and No Viruses are able to multiply, but they require a host in order to create virions. So viruses are able to reproduce, but they cannot reproduce alone, they need a host.

Are viruses able to reproduce? Explain your reasoning.

Answer: Unknown Not enough research has been put in to determine if viruses can react to a stimulus.

Are viruses able to respond to stimuli? Explain your reasoning.

It is best to think of viruses as robots, they do not meet the requirements to be considered living, but they are still able to function, so they are not considered nonliving; however, most would consider viruses more nonliving than living.

Are viruses considered living organisms?

Bigger

As a rule of thumb for transmembrane transportation the bigger the nutrient/waste product that needs to be transported across the cell membrane, the __________________ the transporter needed to move the particle across the membrane.

Torque

As the basal body rotates, the hook exerts _____________________ on the filament, which thereby spins and propels the bacterium forward.

By week 7 of gestation

At what point during gestation does the cartilage in the fetus's skeleton begins to harden into bone?

After week 10 of gestation.

At what point during gestation does the embryo become a fetus?

Day 22 of gestation

At what point during gestation does the heart start beating?

Day 16 of gestation

At what point during gestation does the primitive streak form?

During week 8 of gestation

At what point during gestation will all of the developmental tubes be fully formed?

At week 24 of gestation.

At what point in gestation does the fetus hit the point of having a 50% chance of survival?

Occurs from week 2 of gestation to week 10 of gestation.

At what time does embryogenesis and organogenesis occur during gestation?

Conjugation is the transfer of genetic material from one bacterium to another across a conjugation bridge; a plasmid can be transferred from a donor cell to recipient cells, or a portion of the genome can be transferred from an Hfr cell to a recipient.

Briefly describe conjugation.

-Packaging, modification, and distribution of cellular products (proteins, steroids).

Briefly describe the functions of the following organelle: Golgi Apparatus

-Break down cellular waste -Break down molecules ingested via endocytosis -Apoptosis

Briefly describe the functions of the following organelle: Lysosome

-ATP production -Apoptosis

Briefly describe the functions of the following organelle: Mitochondrion

-Store genetic information -Site of transcription

Briefly describe the functions of the following organelle: Nucleus

-Lipid synthesis -Breakdown of long fatty acid chains -Assist in pentose phosphate pathway

Briefly describe the functions of the following organelle: Peroxisome

Yes, it is possible.

Can the SER able to transport proteins from the RER to the Golgi?

No, the sex factor can also be obtained via transformation.

Can the sex factor only be obtained by a bacteria through conjugation?

Yes The space between the adjacent cells allows for paracellular transport, allowing these cells to transport solute and water without destroying the connection between them.

Can water and solutes be transported between two cells connected via desmosomes? If yes, how so?

Answer: D. The question is asking us to determine at which points in the cell cycle we can prevent or at least lower the number of cells undergoing mitosis. One idea would be to prevent DNA synthesis during the S stage of the cell cycle. Without the DNA being replicated, two viable daughter cells would not be formed. Other ideas would be preventing the mitotic cycle from forming altogether in prophase by preventing spindle apparatus formation, preventing the nuclear membrane from dissolving, or interfering with other processes during this phase. Similarly, a treatment that would act on cells in the metaphase stage of the cell cycle would also interfere with the mitotic cycle. Therefore, any of the three solutions presented would be a viable option.

Cancer cells are cells in which mitosis occurs continuously, without regard to quality or quantity of the cells produced. For this reason, most chemotherapies attack rapidly dividing cells. At which point(s) in the cell cycle could chemotherapy effectively prevent cancer in cell division? I. S stage II. Prophase III. Metaphase A. I only B. I and II only C. II and III only D. I, II, and III

Outer: Phospholipid bilayer contains membrane proteins that allows small molecules to pass through the membrane. Inner: Very impermeable to most molecules. Contains many folds known as cristae.

Contrast between the structure of the inner and outer mitochondrial membrane.

-Microtubules depolymerize -Homologous pairs are pulled away from each other by microtubules pulling them to opposite ends of the cell -Direction the chromosomes of homologous pairs are pulled towards is random.

Describe anaphase I of meisois I.

-Mitotic spindle depolymerizes and pulls sister chromatids to opposite ends of the cell. -Cell begins to stretch out to divide

Describe anaphase of mitosis.

-Cord blood is blood that is taken from the placenta and the umbilical cord after birth of a baby. -The cord blood contains lots of multipotent, or even pluripotent stem cells.

Describe cord blood.

-Chromosomes return to its chromatin form -Indent between the cell gets fully pinched by microfilaments -Two daughter cells are formed and they enter the G1 phase.

Describe cytokinesis.

When a bacterium has its sex factor integrated into its genome the entire genome of the bacteria replicates during conjugation, which is due to the fact that the sex factor is in the cell's genome instead of plasmid. The donor cell will attempt to transfer a copy of its entire genome to a recipient, but the sex pilus degrades before the entire genome can be moved.

Describe high frequency of recombination (Hfr).

Step 1: Sodium is pumped out of the cell and into the blood through the use of the sodium-potassium pump. Step 2: Sodium diffuses back into the cell through the SGLT2 transporter, and provides energy for the transporter to also transport glucose from the blood and into the cell. Step 3: Sodium is pumped out of the cell and into the lumen through the sodium-potassium pump. Step 4: Glucose enters the lumen through facilitated diffusion through the GLUT4 channel protein and into the lumen.

Describe how glucose is absorbed into the lumen of the small intestines through transmembrane transportation.

The neural tube invaginates, at first forming three swelling (prosencephalon, mesencephalon, rhombencephalon) and soon developing into five swellings (telencephalon, diencephalon, mesencephalon, myelencephalon, metencephalon).

Describe how the neural tube differentiates into the different sections of the embryonic brain.

-A method of producing new pluripotent stem cells through gene manipulation of differentiated somatic cells. -Can be used to replace damaged tissues or entire organs. -Patients can have their own pluripotent stem cell line produced from their own somatic cells, meaning that you won't have to worry about immune rejection complications, since the cells originated from the patient.

Describe induced pluripotent stem cells IPS.

-Nuclear envelope completely disappears -Homologous pairs line up along the metaphase plate -Microtubules begin to pull chromosomes in homologous pairs to opposite sides of the cell.

Describe metaphase I of meiosis I.

-Nuclear envelope disappears completely -Chromosomes line up at the metaphase plate in the middle of the cell. -Microtubules begin to pull chromosomes to opposite ends of the cell.

Describe metaphase II of meiosis II.

-Nuclear envelope completely disappears -Chromosomes line up at the metaphase plate in the middle of the cell -Mitotic spindle lines up chromosomes and begins to pull the sister chromatids apart.

Describe metaphase of mitosis.

-Mitotic spindle is formed by the centrosomes and binds to the kinetochore on the centromeres of the chromosomes.

Describe prometaphase of mitosis

-Chromosomes condense -Nuclear envelope starts disappearing -Centrosomes move to opposite ends of the cell -Homologous pairs come together and connect through a group of proteins called the synaptonemal complex -Chromosomal crossover and genetic recombination occurs in this phase -Microtubules polymerize and connect to the kinetochores of the homologous pairs

Describe prophase I of meiosis I.

-Nuclear envelope disappears -Chromosomes condense -Microtubules begin to polymerize and connect to the kinetochores of the chromosomes -Centrosomes migrate to opposite ends of the cells.

Describe prophase II or meiosis II.

-Chromosomes become condensed, chromatin begins to coil up -Nuclear envelope disappears -The two centromeres migrate to opposite sides of the cell

Describe prophase of mitosis.

-Microtubules disappear -Cell starts forming cleavage furrow -Homologous chromosomes are at opposite ends of the cell. -Nuclear envelope begins to form -Chromosomes begin to decondense

Describe telophase I of meiosis I.

-Microtubules disappear -Chromosomes reach opposite ends of the cell -Cleavage furrow begins to form -Chromosomes decondense -Nuclear membrane forms around DNA

Describe telophase II of meiosis II.

-Chromosomes reach the opposite ends of the cell -Mitotic spindle disappear -Chromosomes begin to decondense or unwind -Nuclear membrane begins to form around the DNA -Cell begins to form a cleavage furrow for cytokinesis

Describe telophase of mitosis.

-Phase where cellular division stops permanently -Cells stop dividing and focus on serving their purpose to the body

Describe the G0 phase (no growth phase) of interphase.

-Longest phase of the cell cycle -New cells increase in size after being formed in mitosis -Cells produces organelles for energy and protein production. -Cell will either enter the S phase or the G0 phase after the G1 phase. -Cells must pass a checkpoint in this phase in order to move on to the S phase.

Describe the G1 phase (1st growth phase) of interphase.

-Growth phase that prepares the cell for mitosis/meiosis -Cell starts making microtubules from the centrosomes -Cell must pass a checkpoint that determines if there are enough organelles, cytoplasm, and chromosomes to undergo mitosis/meiosis.

Describe the G2 phase (2nd growth phase) of interphase.

-Involved in the replication of the cell's DNA -Results in the formation of sister chromatids for each chromosome -Sister chromatids are connected to each other by the centromere -Duplication of the centrosomes

Describe the S phase (synthesis phase) of interphase.

-The microfilaments and microtubules of the cytoskeleton are used to move the cell throughout the body. -The polymerization and depolymerization of the microfilaments will cause the leading edge ("front") of the cell to pull the cell in the direction it is heading. -Microtubules in the "back" of the cell will change its rigidity in order to steer and anchor the cell. -If the microtubules are flexible, they are steering the cell. If the microtubules are stiff, they are anchoring the cell, preventing it from moving.

Describe the cytoskeletal model of cellular movement.

Bacterial genetic material is a single circular chromosome which the DNA is wrapped around histone-like proteins. Plasmids are also present, but exists outside of the chromosome.

Describe the genetic material of bacteria.

1. Virus enters the cell; inside the cell, the capsid of the virus dissolved in a process called uncoating, causing the RNA in the capsid to be released. 2. Reverse transcriptase from the retrovirus binds to the RNA of the retrovirus, and reverse transcribes the RNA to form a complimentary DNA (cDNA) strand; reverse transcriptase will then transcribe the new strand of cDNA to produce another strand of cDNA, the two cDNA strands will then come together to form a double-stranded DNA molecule. 3. Integrase from the retrovirus will then remove the 5' and 3' ends from the DNA; by removing them, the DNA will form sticky ends that allows it to be integrated into the host's DNA. Meanwhile, the viral RNA molecule gets degraded by the host's ribonuclease. 4. Viral DNA integrates into the host's DNA and enters a provirus stage like in the lysogenic cycle. Unlike the lysogenic cycle, the viral DNA will not have any repressors that will prevent expression of the viral genome (not dormant/latent). 5. Viral DNA is then transcribed at the same time as host's DNA, which causes the formation of viral mRNA; the viral mRNA will exit the nucleus and get translated by cytosolic ribosomes to form the components of the virus. 6. The viral components are then assembled into new virions, but are immature viruses without an envelope. The virions will obtain an envelope by budding off of the cell in a vesicle from the cell membrane. 7. Protease from the retrovirus will cleave the other two enzymes in the virus to make sure that they are fully functional before the virus enters another cell and infects it.

Describe the life cycle of a retrovirus.

-When virus enters a cell, the genetic material of the of the virus integrates with the host's genetic material. -The genetic material of the virus uses its repressor genes to repress the expression of those genes when integrated to the host's genome. -The virus will not initiate replication until a stimulus is initiated on the cell, like heat or light. -While the virus is latent, the cell will divide, which will lead to the replication of the virus's genetic material into the daughter cells. The genetic material of the virus will be found in the daughter cells of each division. -Virus will stay dormant until it is acted on by a stimulus, like UV light, radiation, or chemicals; at that point, the virus's repressor genes will be weaken, activating the virus's genome, and causes the virus to enter the lytic cycle.

Describe the lysogenic cycle.

-When the virus enters the cell, it immediately begins using the machinery in the cell to start making copies of the virus's genetic material. -Viruses are assembled, and soon causes the cell to lyse when there are too many virions produced for the cell to contain. -When the cell lyses, the virions will then go on to infect other cells.

Describe the lytic cycle.

-Cell endocytoses vesicles from the plasma membrane. -Vesicles are moved to the leading edge ("front") of the cell where they exocytose. -The functionality of the vesicle being exocytosed depends on what the vesicle is made of: *Phospholipid vesicles will cause the leading edge of the cell to extend. *Vesicles containing flip proteins called integrins will anchor the cell membrane to the tissue of an organ, allowing the cell to crawl along and move in that direction.

Describe the membrane flow model of cellular movement.

1. The cell receives apoptotic signals, which causes the pro-apoptotic BCL2 proteins in the mitochondria to activate. 2. The pro-apoptotic BCL2 proteins increases the permeability of the outer mitochondrial membrane. 3. The increased permeability of the outer mitochondrial membrane allows Cytochrome C to exit the intermembrane space and enter the cytoplasm. 4. Cytochrome C will activate caspases in the cytoplasm. 5. Caspases will initiate a controlled cascade of actions, which leads to the degradation of proteins and the activation of other enzymes in the cell, like nuclease. 6. The activation of all the enzymes will lead to the degradation of large polymers inside the cell. 7. The cell will undergo changes in morphology and divides into many self-contained protrusions known as apoptotic blebs, which are then broken apart into apoptotic bodies, which will carry the degraded polymers. 8. Apoptotic bodies are then phagocytosed by other cells, and the materials inside the apoptotic bodies will be recycled by them.

Describe the process of apoptosis.

1. The donor cell containing the sex factor in its plasmid forms a sex pilus for conjugation. 2. The donor cell connects its sex pilus to a recipient cell. 3. The plasmid is replicated in the donor cell through DNA polymerase, and transferred to the recipient cell through the sex pilus. 4. The new plasmid enters the recipient, making it a new donor cell.

Describe the process of conjugation.

1. The primitive streak begins to form on the epiblast, which spans from the caudal (anus) end to the rostral (head) end of the epiblast. 2. Cells at the primitive streak will begin to migrate from the epiblast to the space between the original epiblast and hypoblast, forming the endoderm. 3. The cells of the epiblast that remains next to the amniotic cavity will go on to become the ectoderm. 4. The ectoderm and endoderm close in on each other, and the layer that is formed between the endoderm and ectoderm becomes the mesoderm.

Describe the process of gastrulation in human embryos.

1. A pair of liganda binds to the binding sites of two RTK receptors, activating them. 2. The receptor pairs come together and form a cross-linked dimer. 3. Tyrosine in the enzymatic domain will cause ATP in the cell to become ADP + P. 4. The two RTKs will phosphorylate the tyrosine molecules on one another using the free phosphate group that was cleaved from ATP. 5. Once cross-phosphorylated, the enzymatic domain of RTKs serve as docking stations for different intracellular proteins involved in signal transduction. 6. Bound proteins will cause signal transduction, which travels through the cytosol and ultimately regulates gene transcription, which affects protein production.

Describe the process of the activity of receptor tyrosine kinase (RTK).

1. Bacteriophage injects its genetic material into a bacterium. 2. New viruses are produced from the bacterium, and some of those new viruses will contain genetic material of the cell instead of viral genetic material, known as vectors. 3. Once the bacterium lyses, the bacteriophages are released; vectors go on to inject bacterial DNA into other bacterium. 4. Vector injects genetic material into new bacterium, which is integrated into the host, giving the bacterium new genetic information.

Describe the process of transduction in bacteria.

1. The protein is sent to the Golgi apparatus through a vesicle that buds off from the RER; the vesicle fuses with the cis-face of the Golgi apparatus (the section of the Golgi closest to the RER). 2. Protein undergoes post-translational modifications in the cis-face. 3. Protein is transferred to the medial-face of the Golgi through a vesicle that buds off from the cis-face. 4. Protein undergoes even more post-translational modifications in the medial-face. 5. Protein is transferred to the trans-face of the Golgi through a vesicle that buds off from the medial-face. 6. Protein is then encased in a vesicle from the Golgi and sent to its destination.

Describe the secretory pathway of RER proteins in the Golgi apparatus.

1. Ribosomes will direct specific RNA segments to the RER, where it will be translated into a protein. 2. Protein will then be pushed into the RER, where it will fold into its tertiary or quaternary conformation. 3. Protein will be tagged by a carbohydrate molecule in a process known as glycosylation, which indicates that the protein will be transported to the Golgi apparatus. 4. Protein is encased in a vesicle from the RER, and is shipped to the Golgi apparatus.

Describe the secretory pathway of RER proteins in the RER.

1. Bacterial DNA uses replication enzymes to initiate replication at a spot on the circular chromosome known as the origin of replication. 2. The origin of replication is split in two, with the two origins moving towards opposite ends of the cell. 3. The origins of replication will pull the two chromosomes to opposite sides of the cell. 4. The cell extends, which furthers the separation of chromosomes. 5. Replication continues until the entire chromosome is copied and the replication enzymes meet. 6. Once both chromosomes have moved to opposite ends of the cell and cleared the center of the cell, the membrane pinches inward forming a septum, or a dividing cell wall, in the middle of the cell. 7. The septum splits the cell down the middle, and the two cells are released, forming new bacteria.

Describe the steps in the process of binary fission.

1. The morula begins to differentiate into two types of cells: the trophoblast and the embryoblast. 2. The embryoblast will migrate to one side within the trophoblast, while the remaining cavity will be filled with a fluid to form the blastocoel. 3. The zona pellucida surrounding the blastocyst completely disappear, allowing it to grow and change shape. 4. During the 2nd week of gestation, the embryoblast differentiates into two different layers: the epiblast and the hypoblast, which form the bilaminar disc. The hypoblast will be the layer that will be bordering the blastocoel. 5. The two layers will expand to form two new cavities. The hypoblast will give rise to the primitive yolk sac, while the epiblast will go on to form the amniotic cavity.

Describe the steps of blastulation in the human embryo.

1. Water breaking: The cervix thins out and the amniotic sac ruptures. 2. Birth: Strong uterine contractions, coordinated by postaglandins and oxytocin, results in the birth of the fetus. 3. Afterbirth: The placenta and the umbilical cord are expelled.

Describe the steps of childbirth.

1. Sperm penetrates the corona radiata with acrosomal enzymes 2. Sperm binds to the zona pellucida (known as sperm binding) 3. Sperm releases acrosomal enzymes, which starts to break down the zona pellucida. 4. Sperm binds to the plasma membrane of the ovum after penetrating the zona pellucida. 5. Sperm binding to then plasma membrane causes a release of calcium ions into the ovum, which causes the cortical granules to begin fusing with the plasma membrane. 6. Cortical granules release enzymes that starts digesting the glycoproteins of the zona pellucida (to prevent polyspermy). 7. The head of the sperm fully fuses with the ovum, allowing the sperm to release its genetic material into the ovum. 8. Once the genetic material of both gametes fuse, then we have fertilized the ovum.

Describe the steps of fertilization of a zygote.

1. Haploid sperm and ovum fuse to form diploid zygote. 2. Immediately after the ovum is fertilized, the cell will undergo rapid mitosis until it forms a morula. 3. When the morula gets to around 16 cells or more, the cells in the morula begins differentiating. The outer cells of the morula differentiates into the trophoblast, while the inner cells differentiate into the embryoblast. 4. The entire structure formed is known as the blastocyst in mammals.

Describe the steps of how a fertilized zygote develops.

1. The trophoblast of the blastocyst will come into direct contact with an endometrial cavity known as a crypt. 2. The cells of the trophoblast will begin to proliferate to a point where they start invading the endometrial tissue, causing the blastocyst to be firmly planted into the endometrial lining. 3. Blood vessels in the endometrium will begin to fuse with one another, forming uterine blood vessels. 4. Trophoblast cells begin to differentiate. -Trophoblast cells that grow out into the endometrium become a conglomerate of multi-nucleated cells known as syncitiotrophoblasts. -Trophoblasts that do not form the syncitiotrophoblasts are known as cytotrophoblasts. 5. Syncitiotrophoblasts continue to grow and form projections into the endometrium known as chorionic villi. Cytotrophoblasts will grow along these villi, lining them, leading to the development of fetal blood vessels. 6. Fetal blood vessels migrate close to the uterine blood vessels, which leads to the formation of the placenta.

Describe the steps of implantation.

1. The notochord in the mesoderm causes the ectoderm tissue above it to differentiate and thicken into the neural plate and the neural plate borders. The neural plate extends along the rostral-caudal axis. 2. The neural plate bends back on itself and seals itself into a tube known as the neural tube. The neural plate borders get pulled under the ectoderm along with the neural tube, and becomes the neural crest. 3. The closure of the neural tube disconnects the neural crest cells from the ectoderm. 4. The notochord degenerates, while other mesoderm cells differentiates into somites, the precursors of the axial skeleton and skeletal muscles.

Describe the steps of neurulation that are being shown here.

Electron Transport Chain: 1. FADH2 is oxidized by succinate dehydrogenase, resulting in 2 electrons from FADH2 to be transferred to succinate dehydrogenase. 2. Electrons on succinate dehydrogenase are transferred to Cytochrome Q. 3. Electrons on Cytochrome Q are trasnferred to Cytochrome reductase. 4. Electrons from Cytochrome reductase is transferred to Cytochrome C, which causes Cytochrome reductase to pump 4 H+ from the mitochondrial matrix to the intermembrane space. 5. Electrons from Cytochrome C is transferred to Cytochrome oxidase. 6. Electrons on Cytochrome oxidase is sent back into the mitochondrial matrix, where it reacts with oxygen and H+ to form water. (1/2 O2 + 2 H+ + 2 e- ---> H2O) 2 H+ is pumped from the mitochondrial matrix Chemiosmosis: 7. H+ ions pumped into the intermembrane space will then travel down their concentration gradient into the mitochondrial matrix through the channels of ATP synthase. 8. The travel of H+ through these channels will cause ADP and Pi to collide with each other and form ATP.

Describe the steps of oxidative phosphorylation with FADH2.

Electron Transport Chain: 1. NADH is oxidized by NADH dehydrogenase, resulting in 2 electrons from NADH to be transferred to NADH dehydrogenase. 2. Electrons on NADH dehydrogenase are transferred to Cytochrome Q, which causes NADH dehydrogenase to pump 4 H+ from the mitochondrial matrix to the intermembrane space. 3. Electrons on Cytochrome Q are trasnferred to Cytochrome reductase. 4. Electrons from Cytochrome reductase is transferred to Cytochrome C, which causes Cytochrome reductase to pump 4 H+ from the mitochondrial matrix to the intermembrane space. 5. Electrons from Cytochrome C is transferred to Cytochrome oxidase. 6. Electrons on Cytochrome oxidase is sent back into the mitochondrial matrix, where it reacts with oxygen and H+ to form water. (1/2 O2 + 2 H+ + 2 e- ---> H2O) 2 H+ is pumped from the mitochondrial matrix Chemiosmosis: 7. H+ ions pumped into the intermembrane space will then travel down their concentration gradient into the mitochondrial matrix through the channels of ATP synthase. 8. The travel of H+ through these channels will cause ADP and Pi to collide with each other and form ATP.

Describe the steps of oxidative phosphorylation with NADH.

1. Epinephrine binds to the adrenergic receptor, causing the receptor to undergo a conformational change, and swapping the GDP bound to the alpha subunit of the G protein with GTP. 2. Alpha subunit will dissociate from beta and gamma subunits and seek out the target protein, adenylate cyclase, and activate it. 3. The activated adenylate cyclase will take ATP and produce cAMP (cyclic adenosine monophosphate) by removing two phosphates from ATP. 4. cAMP will leave to act as a 2nd messenger for activating our sympathetic nervous system by breaking down glycogen into glucose for energy.

Describe the steps of the GPCR signalling pathway for epinephrine and an adrenergic receptor.

1. A specific ligand binds to the specific binding site of the GPCR. 2. Once a ligand binds to the GPCR, the GPCR will undergo conformational changes, which causes a complex chain of events that will influence different cell functions. 3. After conformational change, the alpha subunit of the G protein will exchange GDP for GTP. 4. With GTP bound, the alpha subunit will dissociate (move away) from the beta-gamma dimer (beta and gamma subunits of the G protein). 5. Alpha subunit (or occasionally beta-gamma dimer) will then find the target protein in the cell, where it will alter and regulate the function of it. 6. If the target protein is activated, 2nd messengers will be produced and released to carry out a specific function in the body. 7. The GTP on the alpha subunit will be dephosphorylated back into GDP once the reaction is finished, causing the alpha-subunit to rebind to the beta-gamma dimer and return to its inactive state. Ligand leaves the GPCR binding site.

Describe the steps of the GPCR signalling pathway.

Small or nonpolar molecules moving down their concentration gradient Large, polar molecules or charged ions moving down their concentration gradient Any molecule that is moving up their concentration gradient coupled to the hydrolysis of ATP Any molecule that is moving down their concentration gradient and any molecule that is moving up their concentration gradient.

Describe the type of molecules moved and the movement of the molecules for the following forms of transmembrane transportation: Simple diffusion Facilitated diffusion Primary active transport Secondary active transport

1. Cyclin D and Cyclin E proteins are produced in the G1 phase 2. CDK-2 will bind to cyclin E and CDK-4 will bind to cyclin D, forming the CDK-2-cyclin E complex and the CDK-4-cyclin D complex. 3. The two complexes will phosphorylate a protein called RB, which inhibits it from inhibiting DNA replication, allowing the cell to transfer from the G1 phase to the S phase. 4. Cyclin A proteins are produced in the S phase. 5. Cyclin A will bind to CDK-2, forming the CDK-2-cyclin A complex. 6. This complex will then activate the process of DNA replication in the cell.

Describe what happens at the regulation point of the cell cycle between the G1 phase and the S phase.

Once the resources for bacterial growth has been depleted, the environment will no longer be able to support the growth of that colony, and thus bacteria in the colony will perish and the population of the colony will decrease.

Describe what happens during the death phase of bacterial growth.

As bacteria adapts to its environment, it enters a phase where the rate of division increases, causing an exponential increase in bacterial growth in a colony.

Describe what happens during the exponential/log phase of bacterial growth.

The bacteria enters a new environment and bacteria begins to adapt to its new environment; very little bacterial growth occurs in this phase.

Describe what happens during the lag phase of bacterial growth.

As bacterial growth increases, resources to support growth begins to deplete, which leads to a reduce in resources and decrease in bacterial growth; soon, bacterial growth will stop, and plateau.

Describe what happens during the stationary phase of bacterial growth.

It depends on the direction the protein is carrying the molecule. If the molecule is being transported down its concentration gradient, then it does not require energy. If the molecule is being transported up its concentration gradient, then the carrier protein does require energy.

Do carrier proteins require energy to transport a molecule?

Yes, germ cells do undergo mitosis. Germ cells are used in the process of meiosis, but they can also undergo mitosis in order to produce more germ cells to form more gametes.

Do germ cells undergo mitosis?

Answer: Yes Viruses have genes made up of nucleic acids and a capsid made of smaller subunits called capsomeres, thus they have different levels of organization through these smaller building blocks forming a larger product.

Do viruses have different levels of organization? Explain your reasoning.

Answer: Yes and No It takes energy to form new viruses, but the energy needed for replication is provided by the host. So while yes, viruses do use energy for reproduction, they do not produce the energy themselves.

Do viruses use energy for processes? Explain your reasoning.

S-phase of interphase

During which part of the cell cycle does DNA replication take place in?

Between 37 weeks 0 days and 38 weeks 6 days of gestation

During which period of gestation would a newly born offspring be considered early term-term?

Between 39 weeks 0 days and 40 weeks 6 days of gestation

During which period of gestation would a newly born offspring be considered full-term?

Between 41 weeks 0 days and 41 weeks 6 days of gestation

During which period of gestation would a newly born offspring be considered late-term?

After 42 weeks of gestation

During which period of gestation would a newly born offspring be considered post-term?

Before 37 weeks of gestation.

During which period of gestation would a newly born offspring be considered pre-term?

interphase

During which period of the cell cycle does the cell spend most of its life in?

Unipotent, since they can only differentiate into one certain type of cell.

Epidermal stem cells are able to divide and differentiate into skin cells to replace old skin cells that are shed off of the skin. The epidermal stem cells can only differentiate into skin cells. What is the potency of the epidermal stem cells?

Basement membrane

Epithelial cells are attached to something known as the ________________________________, which is not made up of cells, but rather of fibers, specifically collagen.

Avascular Underlying tissue Basement membrane

Epithelial tissue do not have blood vessels directly supplying the tissue with nutrients, meaning that they are _____________________. Because of this, epithelial cells get their nutrients from the __________________________, which travels through the ___________________________, which is semipermeable, and finally reaches the epithelial cells.

Inner lining Outer lining

Epithelial tissue serve as ___________________________ and _____________________________ for organs.

Endothelium

Epithelial tissues that line blood vessels and lymphatic vessels are known as _______________________.

Neurons Resting potential Membrane depolarization Voltage

Excitatory cells such as _______________________ possess voltage-gated sodium ion channels. These channels are closed at a membrane's _______________________ potential, but _________________________ causes changes in the conformation of the channel that allows them to open and close quickly as __________________ increases.

Microfilaments allow the cell to wrap its cell membrane around a substance by extending pseudopods around the substance and form a vesicle around it.

Explain how microfilaments help with the cellular process of endocytosis.

-They have their own DNA -They are able to replicate independently from the cell (self-replicating) -They have their own genome, allowing them to make their own rRNA, tRNA, enzymes in ETC, and produce parts of ATP synthase. -Uses different system of transcription and translation compared to the rest of the cell.

Explain how the mitochondria is relatively independent to the organelles in the cell.

-When DNA polymerase replicates DNA, it does not replicate the DNA strand all the way to the end, which results in the loss of a bit of the telomeres. -Every time the DNA undergoes replication, it loses a little bit more of its telomere, resulting in the telomeres becoming slightly shorter. -After a certain amount of times of cellular division, the telomeres becomes so short to the point of important coding of the DNA becomes at risk of damage from further replication. -When this happens, the cell initiates a DNA damage response, which inhibits the cells ability to copy DNA, essentially causing the cell to lose its ability to divide. This means the cell has become a senescent cell.

Explain why mitotic cells can only divide a certain amount of times.

Answer: B. After an injury, healing occurs by some sort of regenerative process. In humans, some tissues, such as the liver, are capable of regenerating tissue with much the same function and structure as the original tissue. However, the heart is not capable of this sort of regeneration, often forming a fibrous scar in an area of injury. This is an example of incomplete regeneration, in which newly formed tissues are not identical in structure or function to the tissues that have been injured or lost.

Following a myocardinal infraction, the heart often heals by creation of a scar by fibroblasts. This is an example of: A. Complete regeneration B. Incomplete regeneration C. Competency D. Multipotency

Since concentrations outside and inside the cell is not given, we assume the concentrations are equal to the equilibrium potential of the respective ions. K+: Ideal membrane potential = -92 mV 16% = 0.16 0.16 * (-92 mV) = -14.72 mV Na+: Ideal membrane potential: +67 mV 80% = 0.8 0.8 * (+67 mV) = +53.6 mV Cl-: Ideal membrane potential: -86 mV 2% = 0.02 0.02 * (-86 mV) = -1.72 mV Ca(2+): Ideal membrane potential: +123 mV 2% = 0.02 0.02 * (+123 mV) = + 2.46 mV Add all the membrane potentials calculated individually: (-14.72 mV) + (53.60 mV) + (-1.72 mV) + (2.46 mV) = +39.62 mV K+ Na+ Cl- Ca(2+)

For a particular cell, the permeability of ions crossing the cell membrane through ion channels is 16% K+, 80% Na+, 2% Cl-, and 2% Ca(2+). What would be the membrane potential of the cell?

Since concentrations outside and inside the cell is not given, we assume the concentrations are equal to the equilibrium potential of the respective ions. K+: Ideal membrane potential = -92 mV 95% = 0.95 0.95 * (-92 mV) = -87.4 mV Na+: Ideal membrane potential: +67 mV 1% = 0.01 0.01 * (+67 mV) = +0.67 mV Cl-: Ideal membrane potential: -86 mV 2% = 0.02 0.02 * (-86 mV) = -1.72 mV Ca(2+): Ideal membrane potential: +123 mV 2% = 0.02 0.02 * (+123 mV) = + 2.46 mV Add all the membrane potentials calculated individually: (-87.4 mV) + (0.67 mV) + (-1.72 mV) + (2.46 mV) = -85.99 mV K+ Na+ Cl- Ca(2+)

For a particular cell, the permeability of ions crossing the cell membrane through ion channels is 95% K+, 1% Na+, 2% Cl-, and 2% Ca(2+). What would be the membrane potential of the cell?

Activated Inhibited

For adenylate cyclase, if the α-subunit is α(s), then the enzyme is _______________________. If the α-subunit is α(i), then the enzyme is ____________________.

1. Yes 2. No 3. Yes 4. Yes

For aerotolerant anaerobes, answer the following questions: 1. Can it survive in an oxygenated environment? 2. Can it carry out aerobic metabolism? 3. Can it survive in an environment without oxygen? 4. Can it carry out anaerobic metabolism?

Greater, lesser

For channel proteins, if the concentration gradient is __________ inside the cell compared to the environment, then the ions will flow from the cell through the protein and into the environment. If the concentration gradient is ______________ inside the cell compared to the environment, then the ions will flow from the environment through the protein and into the environment.

1. Yes 2. Yes 3. Yes 4. Yes

For facultative anaerobes, answer the following questions: 1. Can it survive in an oxygenated environment? 2. Can it carry out aerobic metabolism? 3. Can it survive in an environment without oxygen? 4. Can it carry out anaerobic metabolism?

Answer: D. Use the Nernst equation to determine the electrical potential. E = 61.5 log [Ca(2+) out] z [Ca(2+) in] z = +2 [Ca(2+) out] = 10000 mM [Ca(2=) in] = 1 mM E = 61.5 log[10000 mM] +2 [1 mM] E = 30.75 log[10000 mM] E = 30.75 * 4 E = +123 mV

For most cells, the extracellular calcium concentration is around 10,000 times higher than the intracellular calcium concentration. What is the membrane potential established by this electrochemical gradient? A. -123 mV B. -61.5 mV C. +61.5 mV D. +123 mV

1. Yes 2. Yes 3. No 4. No

For obligate aerobes, answer the following questions: 1. Can it survive in an oxygenated environment? 2. Can it carry out aerobic metabolism? 3. Can it survive in an environment without oxygen? 4. Can it carry out anaerobic metabolism?

1. No 2. No 3. Yes 4. Yes

For obligate anaerobes, answer the following questions: 1. Can it survive in an oxygenated environment? 2. Can it carry out aerobic metabolism? 3. Can it survive in an environment without oxygen? 4. Can it carry out anaerobic metabolism?

Gram-positive bacterium

From the image shown, what kind of bacterium would this be?

Answer: C. Viruses can exist in either the lytic or lysogenic cycle; they may even switch between them. During the lytic cycle, the virus's DNA takes control of the host cell's genetic machinery, manufacturing numerous progeny. In the end, the host cell bursts (lyses) and releases new virions, each capable of infecting other cells. In the lysogenic cycle, viral DNA is added to the host cell's genome, where it can remain dormant for days or years. Either spontaneously or as a result of environmental circumstances, the provirus can reactivate and enter the lytic cycle. Thus, (A) and (B) are incorrect because the terms are reversed. (D) describes features of bacteriophages, which are viruses that infect bacteria - not the human nervous system. (C) accurately describes how HSV operates during the lysogenic cycle, making it the correct answer.

Herpes simplex virus (HSV) enters the human body and remains dormant in the nervous system until it produces an outbreak after exposure to heat, radiation, or other stimuli. Which of the following statements correctly describes HSV? A. While it remains dormant in the nervous system, the virus is in its lytic cycle. B. During an outbreak, the virus is in the lysogenic cycle. C. HSV adds its genetic information to the genetic information of the cell. D. HSV contains a tail sheath and tail fibers.

Answer: C. For a ligand present in low quantities to have a strong action, we expect it to initiate a second messenger cascade system. Second messenger systems amplify signals because enzymes can catalyze a reaction more than once while they are active, and often activate other enzymes. Both enzyme-linked receptors and G protein-coupled receptors used second messenger systems, while ion channels do not.

Hormones are found in the body in very low concentrations, but tend to have a strong effect. What type of receptor are hormones most likely to act on? I. Ligand-gated ion channels II. Enzyme-linked receptors III. G protein-coupled receptors A. I only B. III only C. II and III only D. I, II, and III

They do not contain any fibers

How are adipose tissues and blood different from other types of connective tissue?

Bacteriophages uses a sheath that they can use to inject their genetic information into a bacteria.

How are bacteriophages able to enter a bacterial cell?

Twins are formed from fertilization of two different eggs released during one ovulatory cycle by two different sperm.

How are dizygotic twins formed?

Through receptor-mediated endocytosis and direct fusion Only through receptor-mediated endocytosis

How are enveloped viruses able to enter a eukaryotic cell? How are non-enveloped viruses able to enter a eukaryotic cell?

Kinetochore microtubules depolymerize and pulls the chromatid to opposing centrioles. Interpolar microtubules initially connect when kinetochore microtubules depolymerize, and then disconnect and depolymerize.

How are microtubules arranged in the anaphase of mitosis?

Kinetochore microtubules are anchored by the centrioles of the centrosomes and polymerizes until they reach the kinetochore of the centromere of a chromosome. Interpolar microtubules are anchored by the centrioles of the centrosomes and polymerizes until they overlap with an interpolar microtubule on the opposite centriole.

How are microtubules arranged in the metaphase of mitosis?

Twins are formed when a single zygote splits in two.

How are monozygotic twins formed?

These agents will create oxidative stress in a cell by reacting to and damaging DNA and lipid-based molecules like cell membranes.

How are peroxides and oxygen radicals (oxygen ions) dangerous for a cell?

Eukaryotic flagella have a 9+2 microtubule structure in its flagella. Prokaryotic flagella have a hollow flagella that is composed of a globular protein known as flagellin.

How are prokaryotic flagella different from eukaryotic flagella?

Prokaryotic ribosomes contain 30S small subunits and 50S large subunits to make 70S prokaryotic ribosomes, while eukaryotic ribosomes contain 40S small subunits and 60S large subunits to make 80S eukaryotic ribosomes.

How are prokaryotic ribosomes different from eukaryotic ribosomes?

-Somatic cells begin with a high capacity for cellular division, but gradually decreases after every round of mitosis due to the shortening of the telomeres of the DNA. -Stem cells also undergo shortening of the telomeres during cellular division, but they also are able to express an enzyme known as telomerase, which is able to reform the bit of telomere that was lost during DNA replication.

How are stem cells able to maintain its capacity for cellular division when somatic cells gradually lose their capacity after every round of mitosis?

Formed from the Golgi Apparatus

How are vesicles formed in exocytosis?

By releasing the enzymes used in the electron transport chain.

How can the mitochondria initiate apoptosis in a cell?

Gap junctions connect cardiac cells in cardiac muscles, which allows the transfer of action potentials through these cells, which allows our heart to continue beating.

How do gap junctions function in cardiac cells?

Gap junctions connect the presynaptic neuron and postsynaptic neuron in the nervous system for the transfer of electrochemical action potentials between the neurons. This only occurs in electrical synapses, not chemical synapses.

How do gap junctions function in the nervous system.

Ligand-gated ion channels rely on the binding of a ligand to the allosteric site of the protein to open and close the channel. Voltage-gated ion channels rely on the difference in membrane potential to open and close. Stretch-activated ion channels depend on the deformation of the cell membrane to open and close (cell membrane stretching).

How do ligand-gated ion channels differ from voltage-gated ion channels and stretch-activated ion channels?

Normal proteins are typically in the shape of an α-helix, while prion proteins are typically in the shape of a β-sheet. When a prion protein comes into contact with a normal protein, the normal protein's conformation is converted from an α-helix to a β-sheet. When more α-helices are converted to β-sheets, it leads to protein deposits aggregating. This build up can lead to interference with biological processes, and lead to decay of organs.

How do prions infect other organisms?

-Oxygen is the final electron acceptor in the electron transport chain in the mitochondria. -Sometimes, oxygens will be improperly reduced in the electron transport chain, which leads to the production of ROS. -If oxidative stress caused by these ROS is too high, the cell will undergo apoptosis.

How do reactive oxygen species (ROS) initiate apoptosis?

An influx of calcium ions causes the heart to contract. The antiporter brings in three sodium ions down its concentration gradient, while pushing out the calcium ion against its concentration gradient to let the heart relax.

How do sodium-calcium exchangers used to restore calcium concentrations in cardiomyocyte (hear cells) after an action potential?

Sodium-potassium pumps will push sodium ions up their concentration gradient, which will cause them to be pushed out of the cell. Sodium ions will then flow down the concentration gradient via simple diffusion through these secondary active transporters. The sodium ions flowing through these secondary active transporters will provide energy to them, allowing them to transport certain molecules against their concentration gradient.

How do sodium-potassium pumps help secondary active transporters?

-Stem cell must express certain genes on the DNA to produce proteins that will allow them to differentiate -Stem cells must also not express certain genes that are not used in the cell it is differentiating into

How do stem cells differentiate into specialized cells?

Centrioles consists of 9 triplets of microtubules around a hollow center, while flagella consists of 9 doublets on the outside, with two microtubules on the inside.

How do the cytoskeletal structures of centrioles and flagella differ?

Transporters do not have analogous Keq values for reactions because there is no catalysis.

How do transport kinetics differ from enzyme kinetics?

-Cells infected by a virus will have certain surface proteins on the surface from the virus. -Immune cells will recognize these antigens and send signals to the infected cell to initiate apoptosis.

How do viral infections initiate apoptosis?

When viroids bind to large numbers of RNA sequences, it can silence genes in the cell's genome. This results in the prevention of the synthesis of necessary proteins, resulting in metabolic and structural damage.

How do viroids infect a host?

Ep = 61.5/z * log([ion out]/[ion in]) z = charge of the ion [ion out] = concentration of ions out of the cell [ion in] = concentration of ions in the cell

How do you determine the electrical potential for an ion?

Vm = Vm(Na+) + Vm(K+) + Vm(Cl-) + Vm(Ca(2+)) Vm(Na+) = 61.5*log(P(Na+) * [Na+ out]) [Na+ in] Vm(K+) = 61.5*log(P(K+) * [K+ out]) [K+ in] Vm(Cl-) = 61.5*log(P(Cl-) * [Cl- in]) [Cl- out] Vm(Ca(2+)) = 30.75*log(P(Ca(2+)) * [Ca(2+) out]) [Ca(2+) in] Vm(ion) = membrane potential of ion P(ion) = permeability of ion with cell membrane [ion out] = concentration of ion out of the cell [ion in] = concentration of ion inside the cell

How do you find the membrane potential of a cell if the concentration of ions in the extracellular and intracellular environment?

The cell uses the phospholipid bilayer of the cell membrane to surround the waste protein, and forming a vesicle. The waste protein is enclosed inside the vesicle, which heads towards the cell membrane. The vesicle fuses with the cell membrane, which opens the vesicle, releasing the protein into the environment.

How does a cell use exocytosis to get rid of waste proteins?

When the new protein is formed inside the cell, it gets integrated into the phospholipid bilayer of the vesicle. The vesicle fuses with the cell membrane, which allows the protein to be directly integrated into the membrane when the vesicle opens.

How does a cell use exocytosis to integrate proteins onto the cell membrane?

If will rapidly divide via mitosis until it forms a mass of cells. Then certain cells will differentiate into different types of cells that will form different parts of the body.

How does a zygote form an organism?

The cell will use extensions of the cytoplasm, known as pseudopods, to surround the pathogen and enclose it in a membrane.

How does an immune cell form a phagosome around the pathogen?

Particle of interest is engulfed into a vesicle formed by the cell membrane, which is then transported into the interior of the cell. Eventually, the particles inside the vesicle are digested, with the nutrients obtained are used to nourish the cell.

How does endocytosis occur?

-If a cell is deprived of oxygen, nutrients, or cellular connections, the cell will initiate apoptosis.

How does environmental stress initiate apoptosis?

Alone, hepatitus D cannot do anything, but when coinfected with hepatitus B, hepatitus D is able to exert a silencing effect on human hepatocytes.

How does hepatitus D viroids affect humans?

-Crossing over of homologous chromosomes -Orientation of homologous pairs along the metaphase plate

How does meiosis increase the genetic variation of gametes?

Phagocytosis is very specific and depends on the cell having the proper receptors it needs to bind to the item it wants to engulf.

How does phagocytosis differ from other methods of endocytosis?

Digoxin is a drug that inhibits the sodium-potassium the sodium-potassium pump in cardiomyocytes. This will lead to an accumulation of sodium ions inside the cell, which will in-turn cause the sodium-calcium exchanger to shift the direction of flow for the ions. This will lead to the sodium ions being pushed out of the cell while calcium ions will flow down the gradient through the exchanger; this will allow more calcium into the cells and result in stronger heart contractions.

How does the drug Digoxin help patients that have atrial fibrilation (an abnormally fast heart rate)?

Answer: B. The outer mitochondrial membrane is very permeable while the inner membrane is highly impermeable. The inner mitochondrial membrane is unique within the cell because it lacks cholesterol.

How does the inner mitochondrial membrane differ from the outer mitochondrial membrane? A. The inner mitochondrial membrane is more permeable and lacks cholesterol B. The inner mitochondrial membrane is less permeable and lacks cholesterol C. The inner mitochondrial membrane is more permeable and has cholesterol D. The inner mitochondrial membrane is less permeable and has cholesterol

The phagolysosome is able to drastically lower the pH of its internal environment, which makes the inside of the lysosome very acidic.

How is a phagolysosome able to break down a pathogen?

-Hands and feel in the fetus are webbed in early development. -The tissue between the digits begin to die off through apoptosis, leading to the development of our digits.

How is apoptosis used in the development of our digits (fingers and toes) in the embryo?

-Stem cells expresses certain genes that allows it to remain undifferentiated -When the stem cell is placed in a certain environment, the expression of those genes can be overwritten, and become differentiated.

How is differentiation triggered in a stem cell?

Vm = 61.5 log (P(Na+)*[Na+ out] + P(K+)*[K+ out] + P(Cl-)*[Cl- in]) (P(Na+)*[Na+ in] + P(K+)*[K+ in] + P(Cl-)*[Cl- out]) Vm = membrane potential P(ion) = permeability of ion across cell membrane [ion out] = concentration of ions outside the cell [ion in] = concentration of ions inside the cell

How is the membrane potential of the cell calculated?

Maintained primarily by the sodium-potassium pump and to a minor extent by leak channels that allow passive transport of ions.

How is the resting membrane potential maintained?

About 20 to 50 divisions.

How many cellular divisions do human somatic cells undergo before apoptosis?

23 46

How many chromosomes are found in a human gamete? How many chromosomes are found in a human somatic cell?

No chromosomes are produced, because the S phase is used to duplicate the DNA of the chromosome, forming sister chromatids. Even though the chromosome has made a copy of its DNA and formed sister chromatids, it is still considered just one chromosome.

How many chromosomes are produced in the S phase of interphase? Explain.

Pumps three Na+ ions out of the cell, up their concentration gradient Pumps two K+ ions into the cell, up their concentration gradient

How many ions does the sodium-potassium pump, and what is their direction in their respective concentration gradient?

Two phospholipid bilayers, an inner membrane and an outer membrane.

How many membranes make up the nuclear envelope?

27

How many microtubules are in a single centriole?

3 trimester 1 trimester = 3 months

How many trimester makes up the period of gestation? How long is a trimester?

Individual virions will only contain one type of nucleic acid.

How many types of genetic material are viruses allowed to have?

Answer: D. Obligate anaerobes cannot survive in the presence of oxygen and would likely be killed by such a therapy, treating the infection. The other types of bacteria listed can all survive in the presence of oxygen, so infections involving these bacteria would likely not be treated using this therapy.

Hyperbaric oxygen may be used as a treatment for certain types of bacterial infections. In this therapy, the patient is placed in a chamber in which the partial pressure of oxygen is significantly increased, increasing the partial pressure of oxygen in the patient's tissues. This treatment is most likely used for infections with: A. Obligate aerobic bacteria B. Facultative anaerobic bacteria C. Aerotolerant anaerobic bacteria D. Obligate anaerobic bacteria

-Endoderm -Ectoderm -Ectoderm -Mesoderm -Endoderm -Ectoderm -Ectoderm -Mesoderm -Mesoderm -Endoderm -Endoderm -Endoderm -Mesoderm -Endoderm -Mesoderm -Endoderm -Endoderm

Identify the germ layer that each of the following are derived from: -Epithelial lining of the gastrointestinal tract -Epidermis -Hair -Muscles -Thyroid -Peripheral nervous system -Central nervous system (brain and spinal cord) -Dermis -Connective tissue (bone, cartilage, adipose, etc.) -Lungs -Stomach -Liver -Kidneys -Bladder -Heart -Bronchi -Large intestines

-Endoderm -Mesoderm -Ectoderm -Mesoderm -Mesoderm -Endoderm -Endoderm -Mesoderm -Endoderm -Ectoderm -Mesoderm -Endoderm -Endoderm -Mesoderm -Ectoderm -Mesoderm -Ectoderm -Endoderm

Identify the germ layer that each of the following are derived from: -Parathyroid -Spleen -Nails -Notochord -Gonads -Epithelial lining of the digestive tract -Pancreas -Circulatory system -Small intestines -Epithelial lining of nose, mouth, and lower anal canal -Musculoskeletal system -Esophagus -Adrenal cortex -Inner ear -Lymphatic system -Lens of the eye -Trachea

A. Epithelial cells B. Basement membrane C. Underlying tissue

Identify the labeled layers in regards to epithelium.

A. Cytotrophoblast B. Amnionic ectoderm C. Amnionic cavity D. Syncytiotrophoblast E. Hypoblast F. Epiblast

Identify the labeled structures in the blastocyst.

A. Zona pellucida B. Blastocoel C. Trophoblast D. Embryoblast

Identify the labeled structures in the blastocyst.

A. Nucleoid Area B. Pili C. Ribosomes D. Inclusion Bodies/Food Granules E. Flagellum F. Plasmid G. Cytoplasm H. Cell Membrane I. Cell Wall J. Capsule/Slime Layer

Identify the labeled structures of the bacterium.

A. Chromosome B. Sister chromatids C. Chromosome D. Centromeres E. Kinetochores

Identify the labeled structures of the chromosome.

A. Prosencephalon (forebrain) B. Telencephalon C. Diencephalon D. Mesencephalon (midbrain) E. Rhombencephalon (hindbrain) F. Metencephalon & myelencephalon G. Spinal cord

Identify the labeled structures of the embryonic brain.

A. Cytoplasm B. Corona radiata C. Zona pellucida D. Cortical granule E. Nucleus

Identify the labeled structures of the ovum.

A. Head B. Midpoint C. Flagellum D. Plasma membrane E. Mitochondria F. Neck G. Centriole H. Nucleus I. Acrosome

Identify the labeled structures of the sperm.

1. Electron Transport Chain 2. Chemiosmosis 3. Oxidative Phosphorylation

Identify the numbered processes being shown here in the inner mitochondrial matrix.

asymmetrical segregation of cellular determinants

Identify the process being shown in the image.

carrier protein

Identify the protein being shown here.

channel protein

Identify the protein being shown here.

Centriole cross section A. Microtubule triplets

Identify the structure shown here. Identify the labeled components of the structure.

Flagella/cilia cross section A. Inner microtubule pair B. Nexin protein C. Outer microtubule pair D. Dynein protein

Identify the structure shown here. Identify the labeled components of the structure.

1. Blastocoel 2. Tophoblast 3. Zona pellucida 4. Embryoblast

Identify the structures of the blastocyst.

Helical

Identify what shape the virus shown is.

Polyhedral/Isohedral

Identify what shape the virus shown is.

Spherical

Identify what shape the virus shown is.

It would be less likely to be infected by another bacteriophage.

If a bacterium is infected by a bacteriophage, is it more likely or less likely to be infected by another bacteriophage (superinfection)?

Expressed Unexpressed

If a gene is turned on in a cell, that gene is ______________________ in the cell. If a gene is turned off in a cell, that gene is _________________________________ in the cell.

Nothing will happen to the cell. Since only one lysosome breaks, the acidic environment of it will be immediately neutralized by the neutral pH of the cytoplasm in the cell. Since the cytoplasm stays at a physiological pH, the digestive enzymes that came from the lysosome will become inactive, meaning that it will not destroy the cell.

If a lysosome breaks inside a cell, what will happen to the cell?

Negative Positive Positive Negative

If a positive ion flows out of the cell, then it will make the membrane potential more _______________________. If a positive ion flows into the cell, then it will make the membrane potential more _________________________. If a negative ion flows out of the cell, then it will make the membrane potential more ___________________________. If a negative ion flows into the cell, then it will make the membrane potential more ____________________________.

Water will diffuse from an area of low solute concentration to an area of high solute concentration in order to balance the molar ratio of solute to solvent.

If a solute in a solution is too big to diffuse across a semipermeable membrane, what will happen instead?

Malignant

If a tumor grows at a rapid rate and becomes invasive, or starts invading other tissues, the tumor is termed __________________________.

begnin

If a tumor grows to a certain size, but does not replicate at a rapid rate that could cause any harm to the body, the tumor is termed __________________.

Yes, it could. Germ cells undergo meiosis to form the gametes of an organism, and the DNA make-up of the gametes are what is passed on to the offspring, given that the gamete with the mutation forms the zygote.

If an organism has a mutation that occurs in a germ cell, would it affect the DNA make-up of the offspring?

No, it would not, since the DNA make-up of somatic cells are not passed off to the organism's offspring.

If an organism has a mutation that occurs in a somatic cell, would it affect the DNA make-up of the offspring?

If many lysosomes were to break at the same time, then the acidic environment from the lysosome will cause the pH of the cytoplasm to decrease. If enough lysosomes were to break to change the pH content of the cytoplasm to 5, then the digestive enzymes of the lysosome will remain active and begin to digest the contents of the cell.

If many lysosomes break inside a cell all at once, what will happen to the cell.

Lyse

If osmotic pressure created by the solutes in a cell exceeds the pressure that the cell membrane can withstand, the cell will ____________________.

Hypotonic

If the concentration of solutes in a cell is greater than the surrounding solution, the solution is said to be __________________________.

Isotonic

If the concentration of solutes inside the cell is equimolar to the surrounding solution, the solution is said to be ______________________.

Hypertonic

If the concentration of solutes inside the cell is smaller than the surrounding solution, the solution is said to be ________________________________.

Conjoined twins

If the division of a zygote is incomplete for monozygotic twins, then ________________________ may result, where the two offsprings are physically attached.

Gram-Positive

If the envelope of the bacteria absorbs the crystal violet stain in Gram staining, and gives off a deep purple hue, the bacteria is _____________________________.

Gram-Negative

If the envelope of the bacteria does not absorb the crystal violet stain, but absorbs the safranin counterstain, and gives off a hot-pink hue, the bacteria is _____________________________.

Cell regulation would be turned off for that cell, and damaged DNA will be replicated at an abnormal rate. This could lead to the development of cancer cells.

If the p53 protein becomes defective in a cell, what would happen?

If the repairs were successful, the cell would reenter the cell cycle. If the repairs were unsuccessful, the cell would destroy itself through apoptosis.

If there is a defect in the genome of the cell, the p53 protein will cause the cell cycle to stop in the G1 phase, providing time for DNA repair. What happens if the repairs are successful? What it it was unsuccessful?

Yes. Antibiotics are used to target parts of bacteria in hopes of killing them, but you cannot kill viruses if they are not living. Instead of destroying the virus, antiviral medicines try to shut off the viral replication cycle.

If viruses are not alive, does that affect how we deal with a viral infection?

Answer: C. Prions are infectious proteins that cause misfoldings of other proteins. Prions generally cause a shift towards β-sheet conformations, causing decreased solubility and increased resistance to degradation. This mechanism is very similar to the one described here for Alzheimer's disease, making (C) the correct answer.

In Alzheimer's disease, a protein called the amyloid precursor protein (APP) is cleaved to form a protein called β-amyloid. This protein has a β-sheet structure and precipitates to form plaques in the brain. This mechanism of disease is most similar to which of the following pathogens? A. Bacteria B. Viruses C. Prions D. Viroids

Inducer Responder

In induction, the ______________________ is the molecule that is released from a cell as a signal for another cell or the cell that is releasing the molecule. The _______________________ is the cell that is being induced in induction.

Haploid germ cells Haploid gametes

In meiosis II, we go from two __________________________ to four ________________________.

Parenchyma Stroma

In most organs, epithelial tissue constitute the functional parts of the organ, known as the ______________________. Meanwhile, connective tissue contributes to the _________________, or support structures.

1. The immune cell bumps into the pathogen accidentally in the blood 2. The immune cell are signaled to move in the direction of the pathogen through chemotaxis, which is initiated by cytokines.

In phagocytosis, how do the pathogen and the immune cell come into contact with each other?

The glucose particles will diffuse to the area of lower concentration.

In the container shown, two separate solutions are separated by a divider. One solution contains a high concentration of glucose, while the other has a low concentration of glucose. If the divider was removed from the container, what will happen to the glucose particles?

Outer

Is the following a characteristic of the inner mitochondrial membrane or the outer mitochondrial membrane? Highly permeable

Inner.

Is the following a characteristic of the inner mitochondrial membrane or the outer mitochondrial membrane? Integral proteins are involved with ATP synthesis and transport chain

Inner

Is the following a characteristic of the inner mitochondrial membrane or the outer mitochondrial membrane? Permeability is restricted

-Lipids -Proteins -Carbohydrates -Nucleic Acids

List the following molecules from most plentiful to least plentiful in the cell membrane: carbohydrates, lipids, proteins, nucleic acids

Sodium ions

Many secondary active transporters use ____________________ to push other molecules against their concentration gradient.

Low temperatures

Membrane fluidity is low at _____________ temperatures.

Carbohydrates Lipids

Membrane receptors are generally proteins, although there are some receptors made out of __________________________ and __________________________.

Alveoli

Name an example of simple epithelium.

Esophagus

Name an example of stratified epithelium.

-Diffusion: Signals are released from one group and diffuses to another group, where they bind to receptors. -Direct contact: One cell can bind to the surface proteins of another cell, causing it to differentiate. -Gap junctions: Signals are passed from one cell to another through gap junctions.

Name and describe the different mechanisms that inductive signalling is carried out.

Glycolysis Process that takes place in the cytoplasm in which glucose, a 6-carbon molecule, is split into two molecules of pyruvate, a 3-carbon molecule.

Name and describe the first process of cellular respiration.

Oxidative phosphorylation (Electron Transport Chain (ETC) and Chemiosmosis). Process that occurs on the inner mitochondrial membrane where NADH and FADH2 are used to generate ATP.

Name and describe the fourth process of cellular respiration.

Pyruvate Dehydrogenase Complex (PDC) Process that takes place in the mitochondrial matrix where pyruvate is converted into acetyl-CoA in order to initiate the Krebs cycle.

Name and describe the second process of cellular respiration.

Krebs Cycle (Citric Acid Cycle) Acetyl-CoA undergoes a series of reactions in the mitochondrial matrix which yields the molecules of NADH and FADH2.

Name and describe the third process of cellular respiration.

Neutrophils Macrophages Dendritic cells B lymphocytes

Name the cells of the immune system that participate in phagocytosis.

1. Glycolysis 2. Pyruvate Dehydrogenase Complex (PDC) 3. Krebs Cycle (Citric Acid Cycle) 4. Oxidative Phosphorylation

Name the four processes that make up cellular respiration.

A. G1 Phase B. G0 Phase C. S Phase D. G2 Phase E. M Phase

Name the labeled phases of the cell cycle.

A. Interpolar microtubule B. Centrioles C. Kinetochore microtubules D. Centromere E. Astral microtubules F. Chromosome

Name the labeled structures of mitosis shown.

A. Nucleic acid B. Capsid C. Sheath D. Tail Fibers

Name the labeled structures of the bacteriophage.

A. Homologous chromosomes B. Centromere C. Kinetochore D. Synaptonemal complex E. Sister chromatids

Name the labeled structures of the homologous chromosome.

1. Ectoderm 2. Endoderm 3. Mesoderm

Name the order of formation of the three germ layers during blastulation.

Phosphatidyl choline

Name the phosphatidyl molecule shown.

Phosphatidyl ethanolamine

Name the phosphatidyl molecule shown.

Phosphatidyl inositol

Name the phosphatidyl molecule shown.

Phosphatidyl serine

Name the phosphatidyl molecule shown.

phosphatidyl glycerol

Name the phosphatidyl molecule shown.

Answer: A. Here, the mutation affects the skin and the nervous system, both of which are derived from the ectoderm. The other germ layers do not lead to skin or nervous system formation, eliminating (B) and (C). The notochord is not actually a primary germ tissue layer, and thus cannot be an answer to the question, eliminating (D).

Neurofibromatosis type I, or von Recklinghausen's disease, is a disorder that causes formation of tumors in multiple nervous system structures as well as the skin. While all cells carry the same mutation on chromosome 17, selective transcription of the genome appears to cause the most significant tumorigenesis in which of the following primary germ tissue layers? A. Ectoderm B. Mesoderm C. Endoderm D. Notochord

Osmosis Primary active transport Exocytosis

Order the following methods of transmembrane transportation from the least amount of energy used to the most amount of energy used: Exocytosis Osmosis Primary active transportation

Not permeable to the membrane.

Osmosis usually occurs when the solute is ___________________________________.

Multipotent, since they can only differentiate into a certain family of cells, blood cells in this case.

Red blood cells have a life cycle of about 4 months, meaning they must be replaced constantly. Our bone marrow contains hematopoietic stem cells that can differentiate into blood cells, but they can only differentiate into blood cells. What type of potency are hematopoietic stem cells?

Answer: C. Bacterial cells reproduce by binary fission, an asexual process in which the progeny is identical to the parent. Therefore, binary fission (Statement I) does not increase genetic variability. Conjugation can be described as sexual mating in bacteria; it is the transfer of genetic material between two bacteria that are temporarily joined. Transduction occurs when fragments of the bacterial chromosome accidentally become packaged into viral progeny produced during a viral infection and are introduced into another bacterium by the viral vector. Therefore, both conjugation and transduction (Statements II and III) increase bacterial genetic variability.

Resistance to antibiotics is a well-recognized medical problem. Which mechanism(s) can account for a bacterium's ability to increase its genetic variability and thus adapt itself to resist different antibiotics? I. Binary fission II. Conjugation III. Transduction A. I. and II. only B. I. and III. only C. II. and III. only D. I., II., and III.

Answer: D. The polarization of the membrane at rest is the result of an uneven distribution of ions between the inside and outside of the cell. This difference is achieved through active pumping of ions (predominantly sodium and potassium) into and out of the cell and the selective permeability of the membrane, which allows only certain ions to cross.

Resting membrane potential depends on: I. The differential distribution of ions across the membrane. II. Active transport processes. III. Selective permeability of the phospholipid bilayer A. I only B. I and III only C. II and III only D. I, II, and III

K+ ions will move down their concentration gradient (i.e out of the cell) until the membrane potential exerts a counterbalancing electrostatic force preventing further K+ movement (the membrane potential returns to its equilibrium potential of -92 mV).

Say that we have a cell that is only permeable by K+ ions and is at its equilibrium potential of -92 mV. If we were able to inject enough positive charge into the cell to lower the membrane potential to -46 mV, what will happen?

Basement membrane

The ______________________ is a thin, delicate membrane that separates an epithelial lining from the underlying tissue.

Blastopore

The ______________________ is the initial opening that is formed during gastrulation.

sodium-potassium pump (Na+/K+ ATPase)

The ______________________ is used to maintain the resting potential of the cell by pumping three sodium ions and two potassium ions against their respective concentration gradients with the use of energy from ATP.

Fatty acid chains

The ______________________ of a phospholipid consists of a carboxylic acid functional group attached to a long carbon chain. It is considered the hydrophobic region of the phospholipid.

Enzymatic domain

The ______________________ of an enzyme-linked receptor is the part of the receptor that acts as an enzyme in a cell.

Golgi apparatus

The _______________________ is a group of membranous sacs near the ER, that is mainly used for the transportation of proteins to the cell membrane.

periplasmic space

The _______________________ is the area between the inner and outer cell membranes in Gram-negative bactera. The peptidoglycan cell wall is found in the ______________________________, and it sometimes contains enzymes to degrade antibiotics.

Basal body

The _______________________ of a bacterial flagella is the structure that anchors the flagellum to the phospholipid bilayer, and acts as a motor for the flagellum.

Umbilical cord.

The _________________________ is what connects the embryo to the placenta, and transfers nutrients & oxygenated blood to the fetus, and waste & deoxygenated blood away from the fetus.

Hook

The _________________________ of a bacterial flagella is the structure that connects the filament and the basal body together.

Filament

The __________________________ is the "tail" portion of the flagella in bacteria.

Cytoskeleton

The __________________________ is the skeleton of a cell that consists of three different types of fibers.

Semipermeability

The ability to allow only certain molecules to cross the cell membrane is known as _________________. Size and polarity of the molecules are factors of this.

Actin polymerization Actin depolymerization

The act of ____________________________________ and _________________________________ is what allows microfilaments to move a cell from the inside of it.

Cell migration

The anterior pituitary gland originates from a section of the oral ectoderm and must move from the top of the mouth to its final location just below the hypothalamus. What is this an example of?

Scramblase transbilayer diffusion

The catalyzed movement of two phospholipids: one migrating from the outer leaflet to the inner leaflet, and another migrating from the inner leaflet to the outer leaflet is known as ___________________________________. Movement uses a protein called scramblase as a catalyst but does not require ATP energy to pull off this movement.

positive

The flow of the concentration gradient of Na+ ions into the cell makes the membrane potential more _____________________.

sphingolipids

The following are examples of ___________________: -ceramides -sphingomyelins -cerebrosides -gangliosides

phosphatidyl molecules

The following molecules can form _____________________ molecules with a phospholipid: -serine -choline -ethanolomine -inocitol -glycerol

Lipid rafts

The function of ______________ are to serve as an attachment point for biomolecules and to assist in cell signalling.

microtubule organizing center (MTOC)

Usually, microtubules will be anchored to a _____________________________________ on one end, while the other end is able to polymerize and depolymerize.

COPII

Vesicle proteins coated in _____________________ are typically sent from the endoplasmic reticulum to the Golgi apparatus.

Microtubules

Vesicles do not migrate randomly to the cell membrane, they are guided there by riding on _____________________ of the cytoskeleton to reach the cell membrane.

Clathrin

Vesicles proteins coated in __________________ are typically sent from the Golgi apparatus to the plasma membrane or lysosome.

They are protein channels linking adjacent animal cells in gap junctions.

What are connexons?

Down Syndrome (Trisomy 21) Klinefelter Syndrome (Two x chromosomes and one y chromosome) Turner Syndrome (Only one x chromosome)

What are examples of diseases caused by nondisjunction during meiosis?

-Oldest of the three domains -Prefer to live in environments with extreme conditions (Extremophiles) -Have different structured cell membranes and cell walls compared to protists and bacteria

What are some characteristics of Archaea?

-Viruses cannot make their own ATP -Viruses cannot reproduce on their own -Viruses do not contain any organelles -Not made up of cells (acellular)

What are some characteristics of a virus that makes it a nonliving infectious agent?

-Category carries a "grab-bag" of unicellular organisms, as well as some multicellular organisms (such as algae) -Only similarities between protists is that they live in moist or aquatic environments.

What are some characteristics of protists?

-Alcohol -Prescription drugs -Viruses -Bacteria -Environmental chemicals

What are some common examples of teratogens?

-Binary fission does not involve the formation and usage of mitotic spindle, unlike in mitosis. -DNA replication and separation happens at the same time in binary fission, whereas it happens in two separate phases in mitosis.

What are some differences between binary fission and mitosis?

Bovine Spongiform Encephalopathy (Mad Cow Disease) Creutzfeldt-Jakob Disease Familial Fatal Insomnia

What are some diseases caused by prions?

-Cardio tissue -Neurons

What are some examples of cells that are post-mitotic?

-Bone -Cartilage -Blood -Lymph -Adipose tissue (fat) -Membranes covering brain and spinal cord

What are some examples of connective tissue?

- Receptor tyrosine kinase (RTKs) - Serine/threonine-specific protein kinases - Receptor tyrosine phosphatase

What are some examples of enzyme-linked receptors?

-Outer layer of skin -Tissue lining mouth, esophagus, and GI tract -Tissue lining kidney tubules -Tissue lining blood and lymphatic vessels. -Outer layer of organs -Lines the lumen of organs -Lines the inside of cavities of the organism -Glands of the body

What are some examples of epithelial tissue?

Sodium-potassium pump (Na+/K+ ATPase) Proton-potassium exchanger (H+/K+ ATPase)

What are some examples of primary active transport?

GLUT4 transporter Ion channels

What are some examples of proteins that participate in facilitated diffusion?

-Superoxide anions (O2-) -Neutrally charged hydroxide molecules (OH) -Hydrogen peroxide (H2O2)

What are some examples of reactive oxygen species (ROS)?

SGLT2 Sodium-Calcium exchanger

What are some examples of secondary active transporters?

-Toxin production -Projections that allow bacteria to attach to certain kinds of cells -Features that allows evasion of host cell

What are some examples of the effects caused by virulence factors in bacteria?

-DNA damage -Infections -Environmental stress -Reactive oxygen species

What are some factors that can induce apoptosis in a cell?

-Telomeres malfunction -DNA damage

What are some other causes of cell senescence outside of the telomeres shortening?

-Both contain a single circular chromosome -Both divide by binary fission or budding -Structures are similar

What are some similarities between Archaea and bacteria?

-Translation starts with the amino acid methionine -Contain similar RNA polymerases -DNA is wrapped around histones

What are some similarities between Archaea and eukaryotes?

-Chromosomes are copied and separated in both processes -The cell divides its cytoplasm to form two new cells in both processes

What are some similarities between binary fission and mitosis?

Synaptic vesicles Vesicles containing proteins and lipids Organelles

What are some substances that kinesin and dynein are able to shuttle around a cell?

Size Shape Genetic Material Type of Host

What are the 4 characteristics that determines a virus's type?

Endoplasmic reticulum Golgi apparatus Lysosome Cell membrane

What are the 4 organelles that are involved in the cellular excretory system?

1. NADH dehydrogenase 2. Cytochrome Q 3. Succinate dehydrogenase 4. Cytochrome reductase 5. Cytochrome C 6. Cytochrome oxidase 7. ATP synthase

What are the 7 enzymes used in oxidative phosphorylation?

Photosynthesizing protists: -Plant-like (algae) Nonphotosynthesizing protists: -Fungus-like (slime molds) -Animal-like (protozoa)

What are the categories that protists are typically classified under?

-Capsid -Nucleic acid -Envelope (sometimes)

What are the components that make up a virus?

-Mitosis produces 2 diploid cells, while meiosis produces 4 haploid cells. -Daughter cells of somatic cells can undergo mitosis, but gametes of germ cells cannot undergo meiosis. -Mitosis has only one phase, while meiosis has two phases. -Gametes produced in meiosis may not have the same genetic information as each other, while daughter cells produced in mitosis will always have the same genetic information as each other. -The daughter cells in mitosis are identical to its parent cell, the gametes in meiosis are not identical to the original germ cell, since each gamete has half as many chromosomes as the germ cell.

What are the differences between mitosis and meiosis?

Dizygotic twins are no more genetically similar than any other pair of siblings, while monozygotic twins are genetically identical. Dizygotic twins will each develop their own placenta, chorion, and amnion. Monozygotic twins may or may not share the same placenta, chorion, or amnion.

What are the differences between monozygotic twins and dizygotic twins?

Prophase I Metaphase I Anaphase I Telophase I

What are the different phases of meiosis I?

Prophase II Metaphase II Anaphase II Telophase II

What are the different phases of meiosis II?

Primary active transport Secondary active transport

What are the different types of active transport?

Simple diffusion Osmosis Facilitated diffusion Filtration

What are the different types of passive transport?

Axial mesoderm Paraxial mesoderm Lateral plate mesoderm intermediate mesoderm

What are the four different sections of the mesoderm?

1. Lag phase 2. Exponential (log) phase 3. Stationary phase 4. Death phase

What are the four phases of bacterial growth?

Activating growth factors in the body Guide developmental processes with tissue structure, placement of nerve endings, and blood vessel maturation. Bind hormones, most notably insulin.

What are the functions of RTKs?

-Provide structural support for tissues -Connect various tissues in the body -Separate different types of tissues in the body

What are the functions of connective tissues?

-Help resist mechanical and chemical stress in the body -Protect the body from pathogens and dessication -Used for absorption, secretion, and sensation in some organs

What are the functions of epithelial cells?

-Transport of water and ions between connecting cells. -Spread electrochemical signals that are produced by action potentials.

What are the functions of gap junctions?

Stores nutrients for bacteria. Stores nutrients that the bacteria picks up from the environment.

What are the functions of inclusion bodies?

Provide structural support for the cell Helps cell resist mechanical stress Anchor organelles in the cell

What are the functions of intermediate filaments?

Gross movement of cell Split the cleavage furrow in cytokinesis Generate muscular movement Initiate endocytosis

What are the functions of microfilaments?

Act as mitotic spindle during mitosis. Construct cilia and flagella Provide a primary pathway for motor proteins such as kinesin and dynein to carry vesicles.

What are the functions of microtubules?

-Modifying proteins made in the RER -Sort and send proteins to their proper destinations -Synthesize certain molecules that need to be secreted from the cell

What are the functions of the Golgi apparatus?

Provide structure for the cell Protect cytosolic contents from the environment Allows cells to act as specialized units Maintain homeostasis inside the cell

What are the functions of the cell membrane?

-Hold cells together while allowing molecules to still pass paracellularly. -Offer space for stress relief in tissues that experiences high amounts of stress (skin and intestines).

What are the functions of the desmosomes?

Separate the nucleoplasm and the cytoplasm Protect genetic information from pathogens, enzymes, and other harmful molecules House molecules used for transcription and DNA repair Facilitate the transport of specific molecules that enter and exit the nucleus.

What are the functions of the nuclear envelope?

Contain the cell's DNA or chromosomes Site of transcription of DNA

What are the functions of the nucleus?

-Repair damaged DNA -Arrest growth of a cell when DNA is damaged, to give enough time to repair DNA -Initiate apoptosis if DNA damage is irreparable

What are the functions of the p53 protein in a cell?

-Isolate peroxides formed as byproducts of enzymatic activity in the cell, and uses catalase to break it down into water and oxygen. (H2O2 ---catalase---> H2O + 1/2 O2 -Break down lipids in cells via β-oxidation -Help detoxify chemicals and drugs in the liver -Assist in synthesis of phospholipids -Enzymes used in pentose phosphate pathway

What are the functions of the peroxisomes?

-Acts as an interface between the mother and the developing fetus -Acts as an exchange system of materials between the fetus and the mother; it separates the two systems, but allows necessary functions to go between them.

What are the functions of the placenta?

-Synthesis of proteins -Post-translational modifications of proteins -Distinguishing which proteins will be integrated into the cell membrane and which proteins will be secreted

What are the functions of the rough endoplasmic reticulum?

-Synthesis of lipids for energy storage, membrane structure, and cellular communication -Synthesis of steroids that act as hormones -Metabolizes carbohydrates -Aids in the detoxification of drugs and other toxins

What are the functions of the smooth endoplasmic reticulum (SER)?

The umbilical vein carries oxygenated blood and nutrients from the placenta to the embryo. The umbilical arteries carries deoxygenated blood and waste from the embryo to the placenta.

What are the functions of the umbilical arteries and umbilical vein in the umbilical cord?

-Form an water-tight layer of cells to contain certain fluids in certain organs from being released in the rest of the body. (Fluid barrier) -Form a fluid barrier that prevents the transport of any substance between both sides of the layer of cells. -Prevent paracellular transport -Form epithelial lining around organs that contain certain fluids like the bladder, kidney, and intestines.

What are the functions of tight junctions?

Organogenesis & Embryogenesis (Development of the heart, eyes, gonads, limbs, liver, and brain)

What are the key developmental features of the first trimester of gestation?

The fetus undergoes tremendous growth Fetus begins to move in amniotic cavity Face becomes distinctly human Digits (fingers and toes) elongate

What are the key developmental features of the second trimester of gestation?

Rapid growth continues Brain development continues Transfer of antibodies from the mother to the fetus

What are the key developmental features of the third trimester of gestation?

-Consist of 7 transmembrane α-helicies (spans the membrane seven times) with a receptor at the beginning. -Interacts with a G protein that is divided into three different subunits. -A GDP molecule that binds with α-subunit of the G protein, which is traded for a GTP when a ligand binds to the receptor.

What are the key structural characteristics of a GPCR?

-Inner plasma membrane -Thin peptidoglycan cell wall -Outer plasma membrane -Lipopolysaccharide layer -Capsule/slime layer

What are the layered structures that are found in a Gram-negative bacterium?

-Inner plasma membrane -Thick peptidoglycan cell wall -Capsule/slime layer

What are the layered structures that are found in a Gram-positive bacterium?

Provide structural support for the cell Assist in movement of the cell Help with the transport of substances in the cell

What are the main functions of the cytoskeleton?

-Flagella -Cell models of movement -Cytoskeletal model - Membrane flow model

What are the methods used for cellular movement?

Alpha subunit Beta subunit Gamma subunit

What are the names of the different subunits of the heterotrimeric G protein of the GPCR?

-Prophase -Prometaphase -Metaphase -Anaphase -Telophase -Cytokinesis (kind of)

What are the phases of mitosis?

-G0 phase -G1 phase -S phase -G2 phase

What are the phases of the cell cycle that make up interphase?

1. Broken down by the lysosome 2. Merge with the cell membrane 3. Excreted into the extracellular environment

What are the possible final destinations for an RER protein in the excretory system?

Microfilaments: Actin Microtubules: α-tubulin and β-tubulin Intermediate filaments: Keratin, desmin, vimentin, lamins

What are the predominant proteins in each cytoskeletal element?

1. Fertilization 2. Cleavage 3. Blastulation 4. Implantation 5. Gastrulation 6. Neurulation

What are the processes that are involved in early embryogenesis? (Place them in order of when they occur).

Pros: -Prevents tumors/cancers from happening by preventing DNA damage. Cons: -Regenerative capabilities of tissues decrease, since mitosis has slowed down. -Senescent cells can lead to age-related diseases like cataracts.

What are the pros and cons of cell senescence?

Asters anchor the centrioles to the cell membrane during cellular division.

What are the purpose of aster microtubules in cellular division?

Opson receptors Scavenger receptors Toll-like receptors Antibodies

What are the receptors that are used during phagocytosis?

1. Living things must maintain homeostasis 2. Living things must have different levels of organization 3. Living things must reproduce 4. Living things must grow 5. Living things use energy 6. Living things respond to stimuli 7. Living things adapt to their environment

What are the seven criteria that something needs to meet in order to be considered a living organism?

Circular double stranded DNA

What are the shape of chromosomes in bacteria?

1. Start by staining the bacterium with a crystal violet stain. 2. Wash the bacterium with alcohol. If the bacterium is still purple, it is Gram-positive. 3. If the bacterium is not purple, we then stain it with the counterstain of Safranin. 4. Wash the bacterium with alcohol. If the bacterium is still a hot-pink color, then it is Gram-negative.

What are the steps in determining if a bacterium is Gram-positive or Gram-negative?

1. Pathogen and the immune cell come into contact with each other 2. The pathogen binds to the cell surface receptor on the immune cell 3. The immune cell starts to surround the pathogen and engulfs it into the cell 4. The surrounded pathogen becomes encased in a vesicle known as a phagosome inside the cell 5. The phagosome fuses with a lysosome, becoming a phagolysosome. 6. Phagolysosome lowers the pH inside it and breaks down the pathogen. 7. Once contents have been neutralized, the phagolysosome forms a residual body that contains the waste product, and releases the waste into the environment.

What are the steps in phagocytosis?

1. 3 Na+ ions bind to the pump from the inside 2. ATP is broken into ADP + Pi by the pump itself, which provides energy to change protein conformation. 3. Protein changes conformation and opens up to the extracellular environment 4. 3 Na+ ions are released on the extracellular side of the membrane 5. 2 K+ ions bond to the pump, which is still activated from ATP hydrolysis. 6. Protein changes conformation and opens up to the intracellular environment 7. 2 K+ ions are released inside the cell

What are the steps of the sodium-potassium pump's function.

-Cells -Ground substance -Fibers

What are the three characteristics that make up connective tissue?

clathrin COPI COPII

What are the three common coats for vesicle proteins?

-Filament -Basal body -Hook

What are the three components that make up the flagella in bacteria?

-Phagocytosis -Pinocytosis -Receptor-mediated endocytosis

What are the three different types of endocytosis?

Microfilaments (7 nm) Intermediate Filaments (10 nm) Microtubules (25 nm) Microfilaments < Intermediate Filaments < Microtubules

What are the three fibers that make up the cytoskeleton? Order them from smallest to largest.

Ligand-gated ion channels G protein-coupled receptors Enzyme-linked receptors

What are the three groups of membrane receptors?

G(s) G(i) G(q)

What are the three main types of G proteins in a GPCR?

Transformation Transduction Conjugation

What are the three methods of genetic recombination in bacteria?

1. Viral invasion initiates cell death. 2. Cell lyses as a result of extremely large numbers or virions produced. 3. Viral extrusion: The virus buds off of the host cell through forming a vesicle from the plasma membrane of the host, resulting in leaving the host alive.

What are the three methods of how virions are released from a host cell?

- A membrane spanning domain that anchors the receptor in the cell membrane. - A ligand-binding domain on the extracellular membrane that binds the ligand -A catalytic/enzymatic domain on the intracellular membrane that acts as an enzyme

What are the three protein domains of an enzyme-linked receptor?

-Specification -Determination -Differentiation

What are the three stages that a cell must go through in order for it to be specialized?

Foregut Midgut Hindgut

What are the three subdivisions of the early digestive tract of an embryo?

Gap junctions Tight junctions Desmosomes

What are the three types of cell junctions?

-Reverse transcriptase -Integrase -Protease

What are the three types of enzymes that are found in the capsid of a retrovirus?

-Simple -Stratified -Pseudostratified

What are the three types of epithelial tissues?

-Thermophiles -Halophiles -Methanogens

What are the three types of extremophiles found in the Archaea domain?

Isohedral/Polyhedral Helical Spherical

What are the three types of shapes of viruses that infect eukaryotic cells?

Endocytosis/Exocytosis Passive transport Active transport

What are the three types of transport in which molecules are able to cross the cell membrane?

Bacteria Archaea Protists

What are the three types of unicellular organisms?

-The cell must be able to self-renew (ability to constantly divide, but at least one of the resulting cells must remain undifferentiated). -Have a high capacity to differentiate into more specialized cells.

What are the two characteristics that a cell needs to have in order to be considered a stem cell?

Lytic cycle Lysogenic cycle

What are the two different patterns of viral replication?

Meiosis I Meiosis II

What are the two different processes that make up meiosis?

Rough endoplasmic reticulum (RER) Smooth endoplasmic reticulum (SER)

What are the two different types of endoplasmic reticulum?

Obligate asymmetric replication Stochastic differentiation

What are the two mechanisms that helps maintain the population of stem cells in the body?

Inner mitochondrial membrane Outer mitochondrial membrane

What are the two membranes that make up the mitochondria?

1. Receptor-mediated endocytosis 2. Direct fusion

What are the two methods for a virus to infect a eukaryotic cell?

Autophagy Crinophagy

What are the two methods of digestion in a lysosome?

Monozygotic (identical) twins Dizygotic (fraternal) twins

What are the two methods of twin formation in development?

Interphase Mitosis

What are the two overarching periods of the cell cycle?

Interphase Mitosis

What are the two overarching phases of the cell cycle?

Internal -Asymmetrical segregation of determinants External -Inductive signalling/induction

What are the two pathways that leads to cell determination?

Alar plate: sensory neurons Basal plate: motor neurons

What are the two plates that make up the neural tube and what structures do each of these plates develop into?

Electron Transport Chain Chemiosmosis

What are the two processes that make up oxidative phosphorylation?

As long as the cell maintains a concentration gradient both in and out of the cell and permeability of the ions responsible for the membrane potential, then it will have a membrane potential.

What are the two things that a cell needs to have in order to have a membrane potential?

Chromatin is made of DNA coiled around proteins known as histones.

What are the two things that makes up chromatin?

1. Anti-apoptotic -Inhibits apoptosis -The balance of BCL2 proteins favor anti-apoptotic proteins when the cell is healthy 2. Pro-apoptotic -Promotes apoptosis -The balance of BCL2 proteins favor pro-apoptotic proteins when the mitochondria receives signals from any of the apoptotic signals.

What are the two types of BCL2 proteins found in the outer mitochondrial membrane, what are their functions, and when are they active in the cell?

Prokaryotes Eukaryotes

What are the two types of cells?

-Indeterminate cleavage -Determinate cleavage

What are the two types of cleavage that are formed in an embryo?

Cyclins Cyclin-dependent kinases (CDKs)

What are the two types of proteins that are used to regulate the checkpoints in the cell cycle?

Positive-sense Negative-sense

What are the two types of single-stranded RNAs that can be found in viruses?

Embryonic stem cells Somatic stem cells

What are the two types of stem cells of a human?

Viroids and Prions

What are the two types of subviral particles?

Immune system Growth Sense of smell Sense of taste Sense of sight Behavior Mood

What bodily functions and senses are regulated by GPCRs?

The Michaelis-Menten equation

What can be used to determine transport kinetics of a ligand-gated ion channel?

Skin blistering

What can mutations in desmosome genes cause to the body?

-Ectodermal dysplasia, which affects the development and functions of teeth, hair, nails, and sweat glands -Breakdown of white matter in the CNS, which can lead to multiple sclerosis and Huntington's disease.

What can mutations in gap junction genes cause to the body?

The lipopolysaccharides in the outer phospholipid bilayer.

What component of a gram-negative bacteria's envelope triggers an immune response in humans?

vesicle-coating proteins, most notably clathrin.

What component on the cell membrane is responsible for the formation of vesicles?

-Cell membrane -Cell wall

What components of a bacteria makes up its envelope?

The antibiotic penicillin targets enzymes that catalyzes the cross-linking of peptidoglycan. Gram-positive bacteria have a thick layer of peptidoglycan and lipoteichoic acid, and contain no outer membrane, whereas gram-negative bacteria have only a thin layer of peptidoglycan but also have an outer membrane containing lipopolysaccharides and phospholipids. Penicillin and antibiotics with similar functions can more easily reach and weaken the peptidoglycan layer of gram-positive bacteria, whereas they would have trouble getting past the outer membrane in gram-negative bacteria.

What difference between the envelopes of gram-positive and gram-negative bacteria make gram-positive bacteria more susceptible to antibiotics such as penicillin?

Hepatitus D

What disease in humans are caused by viroids?

Eukaryotes have membrane-bound organelles.

What distinguishes a eukaryote from a prokaryote?

The inner mitochondrial membrane lacks cholesterol, which differentiates it from most biological membranes, which have cholesterol.

What distinguishes the inner mitochondrial membrane from other biological membranes?

They counteract the change in membrane potential that is caused by the flow of ions down their concentration gradient through leak channels.

What do sodium-potassium pumps counteract in their intracellular and extracellular environment?

It means that a virus needs a host in order to reproduce, and end up causing harm to the host cell.

What does it mean for a virus to be an obligate intracellular parasite?

Dichorionic/diamniotic twins have their own chorions and amnions.

What does it mean if monozygotic twins are dichorionic/diamniotic?

Monochorionic/diamniotic twins share the same chorion, but have different amnions.

What does it mean if monozygotic twins are monochorionic/diamniotic?

Monochorionic/monoamniotic twins share the same chorion and amnion.

What does it mean if monozygotic twins are monochorionic/monoamniotic?

If a cytoskeletal fiber is dynamic, it means that they can become longer through polymerization, and shrink through depolymerization. Dynamic: Microfilaments, Microtubules Not-Dynamic: Intermediate Filaments

What does it mean when a cytoskeletal fiber is dynamic? Which of the cytoskeletal fibers are dynamic, and which of them is not?

It means that the substance is spreading out everywhere in the solution so that it will be evenly distributed.

What does it mean when a substance is moving down its concentration gradient?

It means that the substance is going against the flow of diffusion and is moving to an area of higher concentration of that substance.

What does it mean when a substance is moving up its concentration gradient?

The movement of materials between cells.

What does paracellular mean?

In leukemia, certain blood cells will grow uncontrollably within a patient's bone marrow. This prevents hematopoietic stem cells from producing new blood cells.

What effect does leukemia have on stem cell differentiation?

-Ligand binds to the membrane receptor -Receptor will bind to a protein inside the cell, which causes the protein to change conformation -Results in a cascade of protein signals that alters a cell's behavior

What happens during a signal transduction?

A mutation that causes a loss of function for RB proteins can lead to an increase in cancer cell growth.

What happens if a cell has a defect in RB proteins?

There are bacteria-sized viruses called mamaviruses. These giant viruses has smaller viruses associated with it. When a mamavirus infects an amoebae, it creates a giant virus factory, which will be hijacked by the smaller viruses.

What happens if a virus infects another virus?

Normal proteins will be converted from α-helices to β-sheets, which will lead to protein deposits in the brain. The protein deposits will be cleaned up in the brain, but the aftermath will leave cavities in the place where the protein deposits were. This can lead to loss of certain brain functions and even to symptoms of certain diseases, like dementia.

What happens if prions infect the brain?

Surprisingly, a defect in p21 proteins does not lead to cancer growth, it actually leads to increased regenerative properties in cells (mice have been shown to regenerate full limbs).

What happens if the cell has a defect in p21 proteins?

Substances from inside the cell will leak into the extracellular environment, which can lead to irritation and even an immune response.

What happens in the occurrence of necrosis?

A chemical change occurs inside the cell, which induces an intracellular response.

What happens inside the cell once a ligand binds to a membrane receptor.

Osmosis will cause water to flow into the cell, causing the cell to expand, sometimes to the point of lysing.

What happens to a cell if it is placed in a hypotonic solution?

Osmosis will cause the water to migrate to the outside of the cell, causing the cell to shrivel.

What happens to a cell that is placed in a hypertonic solution?

The membrane potential of the cell changes.

What happens to a cell when a ligand binds to a ligand-gated ion channel?

The conformation of the channel protein will change, either opening up to allow the flow of ions to go to and from the cell or closing up preventing the flow of ions.

What happens to a ligand-gated ion channel when a ligand binds to its allosteric site?

Most often, it will fuse with the phospholipid bilayer, but there are some instances where it would only fuse with the bilayer momentarily.

What happens to a vesicle after the process of exocytosis?

The Golgi apparatus sends the protein back out into the cytoplasm

What happens to cytoplasmic proteins that accidentally enter the Golgi apparatus?

The zygote will undergo rapid mitosis that prevents the cell to actually grow. Each time the zygote undergoes rapid mitosis, the number of cells inside the zona pellucida doubles (1 -> 2 -> 4 -> 8 -> 16 -> 32 -> etc.). The cleavage stage is over once the zygote becomes a morula.

What happens to the zygote during cleavage?

Polyspermy is when multiple sperms bind to the ovum. Polyspermy is bad for fertilization because genetic material from more than one sperm will cause the zygote to fail in forming an offspring. Polyspermy is prevented by the cortical reaction that occurs after a sperm binds to the cell membrane of the ovum. It causes the glycoproteins of the zona pellucida to be digested, meaning sperm will no longer be able to bind to the ovum.

What is polyspermy? Why is polyspermy bad for fertilization? What is done to prevent polyspermy?

Pulmonary edema is fluid accumulation in the alveoli and bronchioles The fluid build up in the alveoli increases the distance that gases must travel to get into the blood, meaning transport of gases decreases.

What is pulmonary edema? How does it affect transmembrane transportation?

Conjugation allows rapid acquisition of genetic information from plasmids that provides advantages, like antibiotic resistance or virulence factors, in a colony.

What is the benefit of conjugation for bacteria?

Primary active transport utilizes energy gained directly from an energy-providing molecule (usually ATP). Secondary active transport utilizes energy gained from a particle going down its concentration gradient.

What is the biggest difference between primary and secondary active transport?

In both autophagy and crinophagy, after molecules are broken down, the contents will be released into the cytoplasm to be reused by the cell.

What is the biggest thing that autophagy and crinophagy have in common?

If during anaphase I or II of meiosis, homologous chromosomes (I) or sister chromatids (II) fail to separate, one of the resulting gametes will have two copies of a particular chromosome and the other gamete will have none. Subsequently, during fertilization, the resulting zygote may have too many or too few copies of that chromosome. Nondisjunction can affect both autosomal chromosomes (such as trisomy 21, which results in Down's Syndrome) and the sex chromosomes (such as Klinefelter and Turner syndromes).

What is the consequence of nondisjunction in meiosis?

Gram-positive bacteria have a thick cell wall composed of peptidoglycan. The cell wall contains long chains of sugars that are connected to each other by proteins. Gram-negative bacteria have a thin cell wall composed of peptidoglycan. Above the cell wall is another phospholipid bilayer (cell membrane) as well as lupopolysaccharide layer above it. The lipopolysaccharide layer contains lipids at the bottom of that layer and polysaccharides (sugar chains) at the top of the layer.

What is the difference between Gram-positive and Gram-negative bacteria?

Slime layers can be washed off, capsules cannot be washed off.

What is the difference between a capsule and a slime layer on a prokaryote?

F+ bacterium contains the F (fertility) factor in their plasmid while F- bacterium lack the F factor.

What is the difference between an F+ bacterium and an F- bacterium?

Determination is the commitment of a cell to a particular lineage. Differentiation refers to the actual changes that occur in order for the cell to assume the structure and function of the determined cell type.

What is the difference between determination and differentiation?

Cytoplasm: Ribosomes will end up in multiple places inside of the cell such as the nucleus, mitochondria, peroxisomes, or just stay in the cytoplasm. RER: Ribosomes will either be secreted into extracellular environment or becoming membrane proteins in the phospholipid bilayer, or they may end up remaining in either the RER, Golgi apparatus, or lysosome.

What is the difference between ribosomes in the cytoplasm and ribosomes in the RER?

Mature somatic cells are already specialized, meaning it is already set in for a specific function, and cannot change its specialization. Somatic stem cells are not specialized, but are used to give rise to more specialized somatic cells.

What is the difference between somatic cells and somatic stem cells?

A cell that undergoes specification can still become any cell type, but a cell that undergoes determination is committed to a certain lineage of cells.

What is the difference between specification and determination.

The centromere connects two sister chromatids. The kinetochore is found on the centromere and connects the chromosome to the mitotic spindle.

What is the difference between the kinetochore and the centromere?

Mitotic cells are able to divide via mitosis, thus they are able to use mitosis as well as somatic stem cells to regenerate tissue. Post-mitotic cells are unable to undergo mitosis, meaning that they can only use stem cells to regenerate tissue. Because of this, mitotic cells are able to regenerate tissue at a faster rate than post-mitotic cells.

What is the difference between the regeneration process for mitotic cells and post-mitotic cells?

Positive ion moving into the cell.

What is the direction of the concentration gradient of Ca(2+) ions in a cell?

Negative ion moving into the cell

What is the direction of the concentration gradient of Cl- ions in a cell?

Positive ion moving out of the cell

What is the direction of the concentration gradient of K+ ions in a cell?

Positive ion moving into the cell

What is the direction of the concentration gradient of Na+ ions in a cell?

+123 mV

What is the equilibrium potential of Ca(2+) ions in a cell?

-86 mV

What is the equilibrium potential of Cl- ions in a cell?

-92 mV

What is the equilibrium potential of K+ ions in a cell?

+67 mV

What is the equilibrium potential of Na+ ions in a cell?

Flagellin

What is the filament in bacterial flagella made of?

Π = i*M*R*T Π = osmotic pressure i = van't Hoff factor M = molarity R = ideal gas constant (0.082 L*atm/mol*K) T = temperature (in Kelvin)

What is the formula to determine osmotic pressure

Has an α(i) subunit Inhibits adenylate cyclase, which decreases levels of cAMP in the cell.

What is the function of a G(i) protein in a GPCR?

Has a α(q) subunit Activates phospholipase C, which cleaves a phospholipid from the membrane to form PIP2. PIP2 is cleaved into DAG and IP3. IP3 is used to open calcium channels in the endoplasmic reticulum, increasing calcium levels in the cell.

What is the function of a G(q) protein in a GPCR?

Has an α(s) subunit Stimulates adenylate cyclase, which increases levels of cAMP in the cell.

What is the function of a G(s) protein in a GPCR?

Use chemotaxis to move bacteria towards nutrients and away from toxins or phagocytes.

What is the function of flagella in prokaryotes?

To provide protection for the fetus, and to act as a shock absorber with amniotic fluid.

What is the function of the amnion?

-Provide cushioning for body -Store energy

What is the function of the connective tissue: adipose tissue (fat)?

-Binds together different types of tissue -Provide flexibility and cushioning for body

What is the function of the connective tissue: areolar tissue?

-Provides support and shock absorption for bones and organs

What is the function of the connective tissue: fibrous connective tissue?

Break down, or lyse, waste products in a cell.

What is the function of the lysosome?

To inject genetic material of the virus into the bacterium.

What is the function of the sheath on bacteriophages?

To maintain the negative resting potential of a cell through removing a positive charge by pumping three Na+ ions out of the cell (up the concentration gradient) and pump two K+ ions into the cell (up the concentration gradient coupled with the hydrolysis of ATP. Essentially keep the extracellular environment more positive than the intracellular environment.

What is the function of the sodium-potassium pump?

To anchor itself to the membrane of the bacterium when injecting genetic material.

What is the function of the tail fibers on bacteriophages?

It allows our cells to control what can enter the cell and what can exit the cell, which allows the cell to maintain homeostasis in its internal environment.

What is the importance of our cells having a semi-permeable cell membrane?

Helps maintain the membrane potential of neurons in the nervous system.

What is the importance of primary active transport in the human body?

Transporters secrete and reabsorb various solutes into and out of the filtrate with the help of sodium ions.

What is the importance of secondary active transport in the human body?

They prevent cells from entering the mitosis phase too frequently, preventing cancerous growths.

What is the importance of tumor suppressor genes in the cell cycle?

The vesicle temporarily fuses with the phospholipid bilayer to release the particle it is holding, and then reform back into the vesicle.

What is the kiss-and-run method in exocytosis?

Answer: B. The first meiotic division (reductional division) pulls homologous chromosomes to opposite poles of the cell during anaphase I. Near the end of telophase I, cytokinesis occurs, resulting in two haploid (n) daughter cells. Thus, during interkinesis and anaphase II, the daughter cells are already haploid, eliminating (C) and (D). The cell is diploid during interphase, (A), but remains diploid up until the end of telophase I.

What is the last point in the meiotic cycle in which the cell has a diploid number of chromosomes? A. During interphase B. During telophase I C. During interkinesis D. During telophase II

Answer: A. The nucleolus (not to be confused with the nucleus) is a dense structure within the nucleus where ribosomal RNA (rRNA) is synthesized. (A) is therefore the correct answer.

What is the main function of the nucleolus? A. Ribosomal RNA synthesis B. DNA replication C. Cell division D. Chromosome assembly

Sperm Ovum (egg)

What is the male sex cell referred to as? What is the female sex cell referred to as?

phospholipid

What is the molecule being shown here?

A mutation of the gene that produces p53, being TP53.

What is the most common mutation found in cancer?

Receptor tyrosine kinases (RTKs)

What is the most common type of enzyme-linked receptor?

Nucleoplasm

What is the name of the fluid on the inside of the nucleus?

Retroviruses

What is the one type of virus that does not undergo either the lytic or lysogenic cycles?

mitochondria

What is the only organelle in the cell that has DNA of its own outside of the nucleus?

There is no pH gradient between the cytoplasm and the intermembrane space because the outer mitochondrial membrane has such high permeability to biomolecules (the proton-motive force of the mitochondria is across the inner mitochondrial membrane, not the outer mitochondrial membrane).

What is the pH gradient between the cytoplasm and the intermembrane space?

pH = 5 The lysosome must maintain this pH in order for its enzymes to function properly, otherwise, they will not be active.

What is the pH inside of the lysosome? Why does the lysosome have this internal pH?

To determine if the DNA in the cell is not damaged so that it may transition from the G1 phase to the S phase for DNA replication.

What is the purpose for the restriction point?

To prevent DNA damage caused by further replication of the DNA.

What is the purpose of cells entering a senescent state?

Cyclins bind to CDKs to activate them. To phosphorylate protein molecules that regulate the cell cycle.

What is the purpose of cyclins in the cell cycle? What is the purpose of CDKs in the cell cycle?

To remove waste proteins from inside the cell.

What is the purpose of exocytosis?

Allow certain ions to flow through it in the direction of their concentration gradient.

What is the purpose of leak channels in the cell membrane?

They contain genes that are not necessary for survival, but may carry some advantages for the bacteria, such as antibiotic resistance and virulence factors.

What is the purpose of plasmids in a prokaryotic cell?

The acrosome is a vesicle at the front of the sperm's head that contains enzymes that allows the sperm to penetrate through the corona radiata and the zona pellucida.

What is the purpose of the acrosome in the sperm?

Gives rise to the esophagus, stomach, first half of the duodenum, and the respiratory bud (which develops into the lungs).

What is the purpose of the foregut?

Gives rise to the second half of the transverse colon, the descending colon, the sigmoid colon, and the rectum.

What is the purpose of the hindgut?

Gives rise to our urogenital system - our kidneys, gonads, adrenal glands, and the ducts that connects these organs.

What is the purpose of the intermediate mesoderm?

Gives rise to the heart, blood vessel, the body wall, and muscles for our organs.

What is the purpose of the lateral plate mesoderm?

Gives rise to the second half of the duodenum, the small intestines, the ascending colon, and the first half of the transverse colon.

What is the purpose of the midgut?

The midpoint of the sperm contains around 75 - 100 mitochondria, which provides energy for the flagellum to move the sperm in a certain direction.

What is the purpose of the midpoint of the sperm?

-Instigates the process of neurulation, which leads to the development of the nervous system. -Defines the major axis of our bodies/determines the midline of our body and separates our left and right side. -Develops into our intervertebral discs.

What is the purpose of the notochord in regards to development?

Gives rise to somites, which differentiates into muscles, cartilage, bone, and dermis.

What is the purpose of the paraxial mesoderm?

To determine if the cell is adequately sized and the organelles have been properly replicated to support two daughter cells.

What is the purpose of the point of regulation between the G2 phase and mitosis?

As osmotic pressure increases, more water will tend to flow into the compartment to decrease solute concentration.

What is the relationship between osmotic pressure and the direction of osmosis through a semipermeable membrane?

It adds more genetic variety for sexual reproduction.

What is the significance of genetic recombination and chromosomal crossing over in prophase I?

Intermembrane space Mitochondrial matrix Acidic: Intermembrane space Basic: Mitochondrial matrix

What is the space between the outer mitochondrial membrane and inner mitochondrial membrane called? What is the space inside the inner mitochondrial membrane called? Of the two spaces, which one is more acidic, and which one is more basic?

Intermembrane space

What is the space between the outer mitochondrial membrane and the inner mitochondrial membrane referred to as?

Saturated phospholipid bilayer

What kind of bilayer is being shown here?

Unsaturated phospholipid bilayer

What kind of bilayer is being shown here?

They use paracrine signalling, in that they diffuse across a gradient in order to reach its target cell.

What kind of cellular signalling pathways do morphogens usually utilize?

RNA replicase, which allows the viral RNA to be replicated in order to form capsomers.

What kind of enzyme does a negative sense RNA virus need to carry in order to reproduce?

Cilia microtubules Flagella microtubules

What kind of microtubules originate from the basal body?

Mitotic spindles: -Kinetochore microtubules -Interpolar microtubules -Astral microtubules Transport microtubules

What kind of microtubules originate from the centrosomes (centrioles)?

Glycoproteins, conjugated protein molecules with carbohydrate prosthetic groups.

What kind of molecules make up the zona pellucida in the ovum?

Capsomers

What kind of proteins make up the capsid of a virus?

-Eukaryotic cells contain membrane-bound organelles with their own specific function (compartmentalization) -Eukaryotic cells have their genetic material encased in a membrane-bound organelle -Eukaryotic cells are generally larger than prokaryotic cells -Eukaryotes can either be unicellular or multicellular, while prokaryotes can only be unicellular -Eukaryotes divide via mitosis, while prokaryotes divide via binary fission

What makes a eukaryotic cell distinct from a prokaryotic cell?

Cancer cells have a defective replication system, meaning they'll continue to mutate and replicate that mutated DNA. So the cancer cells in a tumor will have different types of mutations, meaning it will be hard to develop a drug if mutations keep occurring.

What makes cancer a difficult disease to cure?

Prions are only made up of proteins, meaning they do not have any genetic material.

What makes prions unique compared to viroids and viruses?

Spherical viruses are actually either polyhedral/isohedral or helical viruses surrounded by an envelope. They are considered spherical because of the phospholipid envelope surrounding them.

What makes spherical viruses unique compared to the other two viral shapes?

Intermediate filaments are made up of a variety of proteins, most notably keratin, desmin, vimentin, and lamins. Proteins that make up intermediate filaments are strung together to form a polymer. Polymers will then twist together to form intermediate filaments.

What molecule(s) make up intermediate filaments? Describe how intermediate filaments are constructed?

Microfilaments are composed of a protein known as actin. Many actin molecules will join together to form an actin polymer. Multiple actin polymers will then twist around each other and form an actin filament (microfilament).

What molecule(s) make up microfilaments? Describe how microfilaments are constructed?

Microtubules are composed of two different proteins: α-tubulin and β-tubulin. α-tubulin and β-tubulin will join together and form a dimer. These dimers will then form long chains of the polymers. Then these chains will then be joined together to form a sheet, which is then rolled up to form a microtubule.

What molecule(s) make up microtubules? Describe how microtubules are constructed?

The donor must contain a sex factor known as an F (fertility) factor in order to form a sex pilus.

What must a donor E. coli have in order to form a sex pilus?

The responder must be able to respond to the induced signal, be competent, in order to be induced.

What must a responder be able to do in order to be induced?

The donor must contain a plasmid known as a sex factor in order to form a sex pilus.

What must the donor bacteria have in order to form a sex pilus?

The endoplasmic reticulum

What organelle is continuous with the outer membrane of the nuclear envelope?

The capsomers on the virus's capsid determines its antigenicity.

What part of a virus determines its antigenicity?

Thalamus Hypothalamus Posterior pituitary Pineal gland

What part of the brain does the diencephalon develop into?

Midbrain

What part of the brain does the mesencephalon develop into?

Forebrain

What part of the brain does the prosencephalon develop into?

Cerebral cortex Basal ganglia Limbic system

What part of the brain does the telencephalon develop into?

Anaphase

What phase of mitosis is being shown here?

Metaphase

What phase of mitosis is being shown here?

Prometaphase

What phase of mitosis is being shown here?

Prophase

What phase of mitosis is being shown here?

Telophase

What phase of mitosis is being shown here?

Gastrulation

What process of development is being shown here?

p53 gene

What protein is used to produce p21 and RB inhibitor proteins in the cell cycle?

Spirillum (singular) Spirilla (plural)

What shape of bacteria is being shown here?

bacillus (singular) bacilli (plural)

What shape of bacteria is being shown here?

coccus (singular) cocci (plural)

What shape of bacteria is being shown here?

Neural crest, since it forms cells of the PNS, melanocytes, Schwann cells, calcitonin-producing cells in the thyroid, and some bones & connective tissue of the face.

What structure in early embryonic development is referred to as the 4th germ layer? Explain why.

A centriole

What structure is being shown here?

fatty acid chains

What structure of the phospholipid is being shown here?

glycerol backbone

What structure of the phospholipid is being shown here?

phosphate head group

What structure of the phospholipid is being shown here?

Dormant/Latent

What term is used to describe a virus in the lysogenic cycle?

Virulent

What term is used to describe a virus in the lytic cycle?

Desmosomes.

What type of cell juction is a macula adherens?

desmosomes.

What type of cell junction is a zonula adherens?

Tight junction

What type of cell junction is a zonula occludens?

-Bone cells -Cartilage cells -Adipose cells

What type of cells are produced from mesenchymal stem cells?

-Neurons -Cells that support the nervous system

What type of cells are produced from neural stem cells?

Common in electrically excited cells, such as neurons. The reason why is because these ion channels react really quickly to the binding of ligands, which must be present in cells that need to react quickly to a stimulus.

What type of cells contain ligand-gated ion channels? Why are they present in these types of cells?

Germ cells

What type of cells divide via meiosis to form gametes?

Cells of the immune system When a cell wants to destroy something like a virus, a bacteria, or an infected/dead cell.

What type of cells usually perform phagocytosis? When is phagocytosis used?

-Germ cells -Embryonic stem cells -Tumor cells

What type of cells would contain telomerase?

β-sheets

What type of conformation are prions typically?

Cyclin D and Cyclin E Cyclin D binds to CDK-4, Cyclin E binds to CDK-2

What type of cyclin(s) are produced in the G1 phase? Which CDKs do the cyclin(s) bind to?

Cyclin B Cyclin B binds to CDK-1

What type of cyclin(s) are produced in the G2 phase? Which CDKs do the cyclin(s) bind to?

Cyclin A Cyclin A binds to CDK-2

What type of cyclin(s) are produced in the S phase? Which CDKs do the cyclin(s) bind to?

Indeterminate Cleavage

What type of embryonic cleavage results in the formation of monozygotic twins?

phagocytosis

What type of endocytosis is being shown in the picture?

pinocytosis

What type of endocytosis is being shown in the picture?

receptor-mediated endocytosis

What type of endocytosis is being shown in the picture?

Acid hydrolases They can break covalent bonds of molecules by using a water molecule, but can only do this at an acidic pH.

What type of enzymes are found in the lysosome? What do they do?

Ungated ion channels

What type of ion channel is active at all times?

lateral diffusion

What type of membrane movement is being shown here?

uncatalyzed transbilayer diffusion

What type of membrane movement is being shown here?

Enzyme-Linked Receptor

What type of membrane receptor is being shown here?

G protein-coupled receptor (GPCR)

What type of membrane receptor is being shown here?

cell adhesion molecules (CAMs)

What type of molecules comprises a cell junction?

Glycoproteins (proteins with carbohydrates attached)

What type of proteins are channel proteins on the cell membrane?

Antiporter A calcium ion exits the cell against its concentration gradient while allowing three sodium ions to enter the cell down its concentration. Both calcium and sodium are going in opposite directions.

What type of secondary active transporter is a sodium-calcium exchanger?

Symporter.

What type of secondary transmembrane transporter protein is being shown here?

Channel proteins Carrier proteins

What type of transmembrane protein are able to participate in facilitated diffusion?

facilitated diffusion

What type of transmembrane transportation does GLUT4 provide?

Primary active transport

What type of transmembrane transportation does the sodium-potassium pump (Na+/K+ ATPase) provide?

Facilitated Diffusion

What type of transmembrane transportation is being shown here?

Primary Active Transport

What type of transmembrane transportation is being shown here?

Impenetrable

When a sperm fertilizes an ovum, the wall of the ovum becomes ______________________________.

In the endometrial lining of the uterus

Where does the process of implantation take place in?

Mitochondrial matrix

Where does the pyruvate dehydrogenase complex take place in?

Answer: A. The resting membrane potential is displayed by cells that are not actively involved in signal transduction. Ungated or "leak" channels permit limited free flow of ions, while the sodium-potassium pump is active and corrects for this leakage. Ligand-gated and voltage-gated channels are involved in cell signalling and in the pacemaker potentials of certain cells, but cause deviation from - not maintenance of - the resting membrane potential.

Which ion channels are responsible for maintaining the resting membrane potential? A. Ungated channels B. Voltage-gated channels C. Ligand-gated channels D. No ion channels are involved in maintenance of the resting membrane potential

The epiblast

Which layer of the bilaminar disc is responsible for the formation of the fetus?

Embryoblast

Which mass of cells in the blastocyst is responsible for the formation of the embryo?

Trophoblast

Which mass of cells in the blastocyst is responsible for the formation of the placenta and implantation of the embryo?

Binary fission proceeds more rapidly than mitosis, since there are fewer steps involved.

Which method of cellular reproduction is faster: mitosis or binary fission?

Answer: B. The Golgi apparatus consists of a stack of membrane-enclosed sacs. It receives vesicles and their contents from the endoplasmic reticulum, modifies them (through glycosylation, phosphorylation, and other mechanisms), repackages them into vesicles, and distributes them to appropriate locations in the cell. Protein synthesis occurs in the ribosomes and rough endoplasmic reticulum, eliminating (A). Lipid and carbohydrate breakdown takes place in peroxisomes and cytoplasm, eliminating (C). ATP production occurs in the mitochondria, eliminating (D).

Which of the following activities occurs in the Golgi apparatus? A. Synthesis of proteins B. Modification and distribution of proteins C. Breakdown of lipids and carbohydrates D. Production of ATP

Answer: C. To answer this question, it could be useful to review quickly the embryonic layers. The ectoderm gives rise to the integument (the epidermis, hair, nails, and the epithelia of the nose, mouth, and anal canal), the lens of the eye, and the nervous system (including the adrenal medulla). The endoderm gives rise to the epithelial linings of the digestive and respiratory tracts and parts of the liver, pancreas, thyroid, and bladder. Finally, the mesoderm gives rise to the musculoskeletal system, the circulatory system, the excretory system, the gonads, and the adrenal cortex. Therefore, the only correct association can be found in (C) because the fingernails are derived from the ectoderm.

Which of the following associations of a primary germ layer and an adult organ is correct? A. Endoderm - cardiac muscle B. Endoderm - lens of the eye C. Ectoderm - fingernails D. Mesoderm - lining of the digestive tract

Answer: A. While bones and tendons are composed predominantly of connective tissue cells, muscle tissue is considered a different tissue type. Other examples of connective tissue include cartilage, ligaments, adipose tissue, and blood. Connective tissue often secretes substances to form the extracellular matrix, such as collagen and elastin, eliminating (B). (C) and (D) are essentially identical and can both be eliminated: in organs, connective tissue often forms the support structure for epithelial cells, called the stroma.

Which of the following does not describe connective tissue cells? A. They account for most cells in muscles, bones, and tendons B. They secrete substances to form the extracellular matrix C. In organs, they tend to form the stroma D. In organs, they provide support for epithelial cells

Answer: D. The safest way to answer this question correctly is to go through each answer choice and eliminate the ones that contribute to genetic variability. The random fertilization of an egg by a sperm, the random segregation of homologous chromosomes during anaphase I, and crossing over between homologous chromosomes during prophase I all contribute to genetic variability during sexual reproduction because they result in novel combinations of genetic material, eliminating (A), (B), and (C). S stage, (D), should not cause increased genetic variability; the DNA should be copied precisely, without error, meaning that both strands of DNA should be identical.

Which of the following does not likely contribute to genetic variability? A. Random fertilization of an egg by a sperm B. Random segregation of homologous chromosomes C. Crossing over between homologous chromosomes during meiosis D. Replication of the DNA during S stage

Answer: A. Lysosomes are vesicular organelles that digest materials using hydrolytic enzymes. They are surrounded by a single membrane. Both mitochondria and nuclei are surrounded by double membranes, eliminating (B) and (C). Ribosomes must not be surrounded by membranes because they are found not only in eukaryotes, but also in prokaryotes, which lack any membrane-bound organelles. This eliminates (D).

Which of the following organelles is surrounded by a single membrane? A. Lysosomes B. Mitochondria C. Nuclei D. Ribosomes

Answer: D. The key differences between mitosis and meiosis primarily appear during meiosis I. Of note, synapsis and crossing over occurs during prophase I, and homologous chromosomes are separated during meiosis I (rather than sister chromatids, as in mitosis). While the location of the centromeres relative to the metaphase plate may seem trivial, it is representative of the fact that homologous chromosomes line up on opposite sides of the equatorial plate in meiosis, in contrast to the positioning of each chromosome directly upon the metaphase plate in mitosis.

Which of the following statements correctly identifies a key difference between mitosis and meiosis? A. In metaphase of mitosis, replicated chromosomes line up in a single file; in metaphase II of meiosis, replicated chromosomes line up on opposite sides of the metaphase plate. B. During anaphase of mitosis, homologous chromosomes separate; during anaphase of meiosis I, sister chromatids separate. C. At the end of telophase of mitosis, the daughter cells are identical to each other; at the end of meiosis I, the daughter cells are identical to the parent cell. D. During metaphase of mitosis, centromeres are present directly on the metaphase plate; during metaphase of meiosis I, there are no centromeres on the metaphase plate.

Answer: D. In a virus, the nucleic acid can either be DNA or RNA and - in both cases - can either be single- or double-stranded. Therefore, all of the types of nucleic acids listed here could be used for a viral genome, making (D) the correct answer.

Which of the following types of nucleic acid could form the genome of a virus? I. Single-Stranded RNA II. Double-Stranded DNA III. Single-Stranded DNA A. I only B. II only C. I and II only D. I, II, and III

Pons Cerebellum

Which part of the brain does the metencephalon develop into?

Medulla oblongata

Which part of the brain does the myelencephalon develop into?

Hindbrain

Which part of the brain does the rhombencephalon develop into?

Anaphase I

Which phase of meiosis is being shown here?

Anaphase II

Which phase of meiosis is being shown here?

Metaphase I

Which phase of meiosis is being shown here?

Metaphase II

Which phase of meiosis is being shown here?

Prophase I

Which phase of meiosis is being shown here?

Prophase II

Which phase of meiosis is being shown here?

Telophase I

Which phase of meiosis is being shown here?

Telophase II

Which phase of meiosis is being shown here?

p53.

Which protein is responsible for controlling the restriction point between the G1 and S phases, and regulating the checkpoint between the G2 phase and mitosis?

Meiosis II

Which section of meiosis is the most similar to mitosis?

The neural tube

Which structure in early embryonic development goes on to form the central nervous system?

The neural crest

Which structure in early embryonic development goes on to form the peripheral nervous system?

the alpha and gamma subunits

Which subunits of the G-protein are attached to the cell membrane by lipid anchors?

Plants

Which type of organisms do viroids typically infect?

Passive transport (no energy required) Active transport (energy required)

Which type of transmembrane transport is considered as moving downhill? Which type of transmembrane transport is considered as moving uphill?

They carry materials that came from a cell that underwent apoptosis, which prevents potentially harmful substances from entering the extracellular environment.

Why are apoptotic blebs so important in apoptosis?

To avoid losing any genetic material during cell division.

Why are chromosomes condensed during mitosis?

DNA must be available to RNA polymerases so that genes can be transcribed, thus needs to be decondensed.

Why are chromosomes decondensed in interphase?

The reason why certain classes of cells looks and functions differently from another class of cells is because they each express different genes in the DNA to make different proteins.

Why do certain cells look and act differently from other cells?

Cross-linking activates the tyrosine kinase activity in RTKs through phosphorylation. Each RTK in the dimer phosphorylates the tyrosine on the other RTK,

Why do pairs of RTKs need to cross-link with one another?

Cristae increases the surface area of the inner membrane, allowing for more room for cellular respiration to take place.

Why does the inner mitochondrial membrane have so many folds (cristae)?

Because the H+ ions that are pumped out of the mitochondrial matrix during the electron transport chain.

Why does the intermembrane space of the mitochondria have a low pH?

Chemotherapy and radiation target cells that are fast growing, which is the common theme of cancer cells.

Why is chemotherapy and radiation used to treat cancer?

HIV is a type of retrovirus. Retroviruses have an enzyme known as reverse transcriptase, which allows the virus to transcribe its RNA into cDNA. However, the reverse transcriptase will frequently make mistakes in the coding of cDNA from RNA, leading to many mutations to develop for the retrovirus. A drug that may have worked for a previous generation of HIV may not work for the next generation of HIV due to mutations caused by reverse transcriptase.

Why is it hard for a vaccine to be developed for HIV?

The pump in of itself also acts as an enzyme for the hydrolysis of ATP.

Why is the sodium-potassium pump also referred to as Na+/K+ ATPase?

Integral Proteins

____________ proteins are proteins that cross entirely through the phospholipid bilayer of the cell, making them difficult to remove. They allow certain molecules to be transported in and out of the cell.

Cholesterol

_____________ is a major component of a cell membrane, where it increases fluidity of a cell membrane at low temperatures and decreases fluidity of a cell membrane at high temperatures.

TP53

_____________ is the gene in a cell that produces p53 proteins.

Uncatalyzed movement

_____________ movements do not require a catalyst in order for the phospholipids to move around the cell membrane.

lipid rafts

______________ are collections of similar lipids with or without associated proteins that serve as attachment points for other biomolecules and for signal transduction.

Glycoproteins

______________ are molecules that consists of a carbohydrate bound to a membrane protein that are used in cell signalling.

Unsaturated fatty acids

______________ fatty acids increases fluidity in the cell membrane, because the double bond in its carbon chain causes the phospholipids to space out from one another.

Protein

______________ is a major component of the cell membrane that is used as receptors and for facilitating transportation of molecules in and out of the cell.

Saturated fatty acids

_______________ fatty acids decreases fluidity in the cell membrane, because its uniform single bonded carbon chain allows phospholipids to stack neatly with one another.

Phosphatidyl glycerol

_______________ is the only phosphatidyl molecule that has two phosphatidyl groups that bonds the molecule to two phospholipids.

Charged molecules

_______________ molecules are unable to pass through the cell membrane directly, due to their polarity. These molecules can only enter the cell through a channel protein. Examples include sodium ions and chloride ions.

Catalyzed movement

_______________ movements require the use of a catalyst to expend energy for movement in the cell membrane. Catalyst in this case would be a protein, such as flippase, floppase, and scramblase.

Carrier proteins

_______________ proteins are integral proteins that "carries" certain molecules through the cell membrane. These proteins will encapsulate the molecule, protecting the molecule for safe entry or exit of the cell, and release it. Transportation of molecules is able to go against the concentration gradient, but may require the use of ATP.

Lipid-bound proteins

_______________ proteins are proteins found within the hydrophobic portion of the phospholipid bilayer. Because these proteins are unable to carry out their outer membrane functions, their presence is extremely rare in most cells.

Small, nonpolar molecules

_______________, ______________ molecules are the only type of molecule that can move easily through the cell membrane directly due to its size and polarity. Examples includes gases such as O2 and CO2.

Small, polar molecules

_______________, _______________ molecules are able to pass through the cell membrane directly, but can only travel slowly since they are not very compatible with the hydrophobic region of the phospholipid bilayer. Examples include water and ethanol.

Hemidesmosomes

________________ are a type of desmosome that attached epithelial cells to underlying structures, especially the basement membrane.

Carbohydrates

________________ is a major component of the cell membrane that assist with cellular communication outside the cell, and the formation of a protective glycoprotein coat on the cell membrane. They bind to proteins and lipids on the membrane.

paracellular transport

________________ is the transport of materials through the interstitial space without interactions with the cytoplasm or cellular membrane.

Channel proteins

________________ proteins are proteins that has a channel in it that transports ions that cannot cross the cell membrane in and out of the cell. They require no ATP for transportation, but the flow of transportation is dependent on concentration gradient.

Large, nonpolar molecules

________________, ________________ molecules are able to pass through the cell membrane directly, but can only travel slowly since their size gives them difficulty for passing between the phospholipids in the membrane. An example of this is benzene.

Large, polar molecules

________________, ________________ molecules are unable to pass through the cell membrane directly, due to its size and polarity. These molecules can only enter the cell through a carrier protein. An example of this is glucose.

desmosomes

_________________ are cell junctions that are thread-like substances that bind adjacent cells by anchoring to their cytoskeletons.

Haploid (n) Diploid (2n)

_________________ are cells that have half of the full set of chromosomes in a cell, while ____________________ are cells that have the full set of chromosomes in a cell.

Cilia

_________________ are hair-like projections from a cell that is composed of microtubules, and are used in the movement of materials that are outside of the cell.

Centrioles

_________________ is a cell organelle found in the centrosome that aids in cell division in animal cells.

nexin

_________________ is a protein found in cilia and flagella that crosslinks microtubule doublets to keep them in place, allowing the structure to bend.

p53

_________________ is a tumor suppressor protein that causes cell cycle arrest in G1, providing time for DNA repair. If repair is successful, cells re-enter the cycle. If unsuccessful, apoptosis

p21

_________________ is an inhibitor protein of cyclin-cdk complexes, preventing them from activating DNA replication or mitosis.

ground substance

_________________ is the fluid or semi-fluid portion of the matrix in connective tissue.

Sperm Ovum (egg cell)

_________________ is the male gamete in humans. ________________ is the female gamete in humans.

Endocytosis

_________________ is the process of which the cell transports molecules from outside the cell to the inside of the cell.

Peripheral proteins

_________________ proteins are proteins that are able to attach and detach themselves from the cell membrane, and is used for various cell processes. They are typically found either on top of the membrane, slightly in the membrane, or on top of another protein.

Plasmids

__________________ are extra pieces of DNA in bacteria that is found outside of the nucleoid region.

Transposons

__________________ are short strands of DNA capable of moving from one location to another within a cell's genetic material (jumping genes). It is not limited to only prokaryotes, it is found in eukaryotes as well.

Ligand

__________________ are the substances that can bind to a membrane receptor of a cell.

Pinocytosis

__________________ is a type of endocytosis in which the cell ingests extracellular fluid and its dissolved solutes (cell drinking).

Specification

__________________ is the initial stage of cell specialization in which the cell is reversibly designated to a specific cell type

Biosignalling

__________________ is the process in which cells receive and act on signals.

Chiasmata

__________________ is the segment of the two homologous chromosomes where crossing over takes place in; it keeps the homologues connected to each other after the synaptonemal complex breaks down.

Proton pump

___________________ are active transport proteins in the cell membrane that uses ATP to transport hydrogen ions out of a cell and potassium into the cell against their concentration gradient, generating a membrane potential in the process.

Flagella

___________________ are tail-like projections from a cell that is composed of microtubules, and are used to move the cell in its environment.

Chromosomes

___________________ are thread-like molecules that are made of fibers known as chromatin.

Apoptosis Necrosis

___________________ is cell death initiated by the cell itself. __________________ is cell death that is initiated by extreme stress, like from an extreme infection or extreme trauma.

Chemotaxis

___________________ is the sensing of chemicals through the flagella, and responds to these chemicals by either moving towards or away from it.

Nucleocapsid

___________________ is the term used for a capsid that has a nucleic acid in it.

Gap junctions or connexons

____________________ are cell junctions that are essentially tubes that join two adjacent cells together, where both cells can transport water and ions between each other.

Unregulated channels

____________________ are ion channels that have no gates on them, thus leaves them unregulated.

Voltage-gated channels

____________________ are ion channels where the gate is regulated by membrane potential changes near the channel.

SGLT2

____________________ is a glucose transporter found in cells in the intestines that allows glucose to enter the cell against its concentration gradient by letting a sodium ion to enter the cell and travel down its concentration gradient. Both sodium and glucose are entering the cell.

Retinoblastoma protein (RB)

____________________ is a tumor-suppressor protein that helps regulate progression of a cell from the G1 phase to the S phase of the cell cycle by inhibiting DNA replication and repress the growth of tumors.

Pinocytosis

____________________ is the endocytosis of dissolved ions and solutes in the liquid medium surrounding the cell.

Phagocytosis

____________________ is the endocytosis of large substances such as bacteria or other pathogens.

Capsid

____________________ is the outer protein coat of a virus.

Uncoating

____________________ is the process of a virus's capsid being dissolved in a cell, causing the release of its genetic material.

Fertilization

____________________ is the process of when a sperm cell fuses with an ovum.

GLUT4

____________________ is the transport channel for glucose found in muscle cells and fat cells that opens after insulin binds to the insulin receptor. Used to transport glucose from the blood and into the cell without the use of energy.

Exocytosis

____________________ is the transport of molecules out of the cell by release of a transport vesicle; the vesicle will fuse to the cell membrane during secretion. It requires a lot of energy to use.

Gametes

_____________________ are haploid sex cells that are produced through the meiosis of germ cells.

Membrane receptors

_____________________ are integral proteins embedded in the cell membrane that takes part in communicating with the outside environment.

Sphingolipids

_____________________ are lipids in the cell membrane that are similar in structure to phospholipids, except they have an amino alcohol group as a backbone instead of glycerol.

Prions

_____________________ are proteinaceous infectious particles, or subviral particles made up of proteins.

Telomeres

_____________________ are repeated, duplicate DNA sequences that are found at the very tips of chromosomes and that prevents damage to the DNA during DNA replication.

Viroids

_____________________ are subviral particles that are made up of a single strand of circular RNA.

Mitochondria

_____________________ are the organelle that is responsible for producing ATP in the cell.

dynein

_____________________ is a large contractile protein forming the side-arms of microtubule doublets in cilia and flagella. They break down ATP and use energy for microtubules to move pass each other, which drives the movement of the flagella and cilia.

sodium calcium exchanger

_____________________ is a transport protein in the membrane of many cells that pumps one calcium atom out of the cell against its concentration gradient in exchange for three sodium ions moving into the cell down their concentration gradient

Phagocytosis

_____________________ is a type of endocytosis in which a cell engulfs large particles or whole cells (cell eating).

Neoplasm/Tumor

_____________________ is an accumulation of abnormally dividing cancer cells.

Endoplasmic reticulum

_____________________ is an organelle that is continuous with the outer layer of the nuclear envelope.

Regenerative capacity

_____________________ is the ability of an organism to regrow certain parts of the body.

Chromatin

_____________________ is the decondensed form of chromosomes found in interphase, these fibers are not coiled up in interphase and are not visible in light microscopy.

Ploidy

_____________________ is the number of sets of chromosomes in a cell

Mitosis

_____________________ is the process in which the nucleus of the cell separates into two nuclei that each contain the original genetic information in the cell.

single crossover

_____________________ is the sharing of DNA between homologs at one location.

parturition

_____________________ is the term used to describe vaginal childbirth.

Mitotic cells.

______________________ are cells that are actively able to divide and are able to regenerate tissues they are a part of via mitosis.

Cancer cells

______________________ are cells that divide at an abnormal rate, resulting in the formation of a neoplasm/tumor.

Virions

______________________ are individual virus particles.

chorionic villi

______________________ are microscopic finger-like projections that penetrate the endometrium; it develops into the placenta & support maternal-fetal gas exchange

Toll-like receptors

______________________ are phagocytic receptors of the innate immune system that recognizes structures of previously encountered pathogens, and activate an inflammatory response when the pathogen is identified.

Antibodies

______________________ are phagocytic receptors that are made by immune cells that bind to the antigen on the surface of a pathogen to alert the immune system to respond appropriately to combat the threat.

Nucleosomes

______________________ are repeating subunit of chromatin fibers, consisting of DNA coiled around histones

Reactive Oxygen Species (ROS)

______________________ are various oxygen species formed as a byproduct of metabolism that are highly reactive due to the unpaired electron shell. The reactivity of these species are capable of breaking down a cell.

Lysosome

______________________ is a spherical organelle that contains enzymes that hydrolizes substances that crosses its membrane, so that the contents can be reused in the cell.

Zona pellucida

______________________ is a thick layer of glycoproteins that functions as a protective layer for the ovum that the sperm must penetrate in order to fertilize it.

Vector

______________________ is a virus that carries genetic material from one bacterium to another.

Secondary active transport

______________________ is an active transport that harnesses the energy released by a particle going down its concentration gradient to drive a different particle up its concentration gradient.

peroxisome

______________________ is an organelle that takes toxic peroxides that are formed from various cellular activity and breaks it down into water and oxygen with the use of the enzyme catalase.

Nucleolus

______________________ is the dense region of the nucleus that produces ribosomal RNA (rRNA) and synthesizes ribosomes with rRNA.

Direct fusion

______________________ is the method for a virus to enter a eukaryotic cell by fusing their envelope to the cell membrane as if it were a vesicle; this allows the virus to be released into the cell once the envelope fuses.

Synapsis

______________________ is the pairing of homologous chromosomes during meiosis

Autolysis

______________________ is the process in which the lysosomes in a cell releases their hydrolytic enzymes into the cytoplasm, resulting in apoptosis of the cell.

Amnion

______________________ is the thin, tough membrane that forms the amniotic cavity, which is filled with amniotic fluid.

Sister chromatids

______________________ refers to the two copies of DNA on a chromosome when it replicates in the S phase.

Post-mitotic/non-mitotic cells

_______________________ are cells that are unable to undergo mitosis, thus their ability to regenerate is limited to only stem cells.

Nuclear pores

_______________________ are channel proteins that dot the nuclear envelope that facilitates what molecules, such as mRNA and ribosomes, may enter or exit the nucleus.

Cell junctions

_______________________ are different connections between cells that can perform a variety of functions for the body.

kinetochore microtubules

_______________________ are microtubules that are anchored to the centrosome that attaches to the kinetochore on a chromosome in mitosis, and pulls the chromosomes to opposite poles of the cell.

morphogens

_______________________ are molecules that are released from a cell that causes nearby cells to proceed in a specific developmental pathway during embryonic development. Used during induction/inductive signalling, and induces differentiation in the cell.

Bacteriophage

_______________________ are viruses that infect bacteria.

Nucleus

_______________________ is a eukaryotic membrane-bound organelle that contains the cell's genetic code.

Telomerase

_______________________ is a reverse transcriptase that is able to synthesize new components of the telomeres at the ends of chromosomes, preventing cell senescence.

senescenece

_______________________ is the change of a cell from being able to perform mitosis to it being unable to perform mitosis.

Membrane potential

_______________________ is the difference in electrical potentials between the exterior and interior of the cell membrane caused by the concentration of ions in both environments.

Plasma

_______________________ is the matrix of the connective tissue: blood.

Hydroxyapatite

_______________________ is the matrix of the connective tissue: osseous/bone tissue.

Autophagy

_______________________ is the process in which lysosomes digest damaged organelles to reuse the molecules for the cell.

double crossover

_______________________ is the sharing of DNA between homologs at two locations.

Metastasis

_______________________ is the spread of cancer cells to locations distant from their original site.

Interkinesis

_______________________ refers to the interphase that occurs between meiosis I and meiosis II.

Antigenicity

_______________________ refers to the part of the substance that stimulates the activity of white blood cells.

Caspases

________________________ are a type of protease that breaks down proteins after the aspartate residue by using a cysteine residue.

mechanosensitive (stretch) channels

________________________ are channel proteins that open in response to mechanical forces acting on the membrane, usually when the cell membrane stretches.

Cuboidal cells Columnar cells Squamous cells

________________________ are epithelial cells that are cube-shaped _______________________ are epithelial cells that are long and thin ________________________ are epithelial cells that are flat and scalelike

opsonin receptors

________________________ are phagocytic receptors are used to bind bacteria or other particles that have been coated with immunoglobulin G (or "IgG") antibodies by the immune system.

Cytokines

________________________ are small proteins that signal immune cells to move to a certain area in the body where the pathogen can be found.

Desmosomes

________________________ can hold cells together, but it does not seal other molecules from passing.

autocrine signaling

________________________ is a form of cellular communication where the signal acts on the same cell that secreted the signal in the first place.

Morula

________________________ is a mass of cells that is formed after the zygote has undergone cleavage a certain number of times.

Syncitiotrophoblast

________________________ is a structure that differentiates from the trophoblast into the surrounding uterine tissue during implantation.

Receptor-mediated endocytosis

________________________ is a very specific method of endocytosis involving the uptake of specific molecules based on a cell's receptor protein.

Adhesion

________________________ is an action in implantation where the cells of the trophoblast begins to proliferate into the endometrial tissue, causing the blastocyst to be firmly planted into the tissue.

Nondisjunction

________________________ is an error in mitosis or meiosis in which members of a pair of homologous chromosomes or a pair of sister chromatids fail to separate properly from each other, causing one daughter cell or gamete to have more chromosomes than the other.

Indeterminate cleavage

________________________ is the cleavage that results in cells that can still develop into complete organisms.

BCL2 family proteins

________________________ is the family of proteins that regulates the permeability of the outer mitochondrial membrane.

blastocoel

________________________ is the fluid-filled cavity inside a blastula.

Transformation

________________________ is the integration of foreign genetic information from the bacteria's environment and into its own genome.

Embryoblast Trophoblast

________________________ is the mass of cells found inside of the blastocyst. ______________________ is the layer of cells that forms the walls of the blastocyst.

Binary fission

________________________ is the method of which bacteria reproduce by undergoing cellular division.

Lytic cycle

________________________ is the replication process for viruses where replication immediately begins, resulting in the death of the host cycle.

Notochord

________________________ is the thin rod of cells that is formed in the mesoderm, which gives rise to the development of the nervous system.

Prophage/Provirus

________________________ is the viral DNA that is embedded in the host cell's DNA.

Stochastic differentiation

________________________ is when a stem cell divides into two differentiated cells, another stem cell undergoes mitosis to produce two more stem cells to make up for the loss of the first stem cell.

Hayflick limit

________________________ refers to the number of times a cell can divide before reaching replicative senescence.

Catalytic RNA

_________________________ are RNA molecules that can make or break covalent bonds, viroids are considered to be this type of RNA.

Obligate anaerobes

_________________________ are bacteria that use fermentation or anaerobic respiration to carry out metabolism. They cannot use oxygen; an oxygenated environment will kill the bacteria.

Tight junctions

_________________________ are cell junctions that are formed when the membranes of neighboring cells are pressed together very tightly, where contents are not transferred between cells.

Methanogens

_________________________ are organisms that synthesize methane from carbon dioxide and hydrogen gas, and are commonly found in swampy areas.

Multipotent stem cells

_________________________ are stem cells that are able to differentiate into any cell within a specific cell family.

Triacylglycerols (triglycerides)

_________________________ are storage lipids that consist of 3 fatty acid chains bound to a glycerol molecule through an ester bond, without a phosphate head group.

Bacteriophage

_________________________ are viruses that infects bacteria only.

Ligand-gated ion channel

_________________________ is a type of membrane receptor in the plasma membrane that opens or closes in response to a chemical signal, allowing or blocking the flow of specific ions.

Contact inhibition

_________________________ is the cessation of cellular division in response to contact with other cells.

Determinate cleavage

_________________________ is the cleavage that results in cells with fates that are already determined.

Embryogenesis

_________________________ is the development of the embryo.

Receptor-mediated endocytosis

_________________________ is the method for a virus to enter a eukaryotic cell by binding to a receptor on the cell membrane, which causes the virus to be encased in a vesicle and taken into the cell.

Diffusion

_________________________ is the movement of solutes from a higher area of concentration to a lower area of concentration (moving down the concentration gradient).

Transduction

_________________________ is the only method of genetic recombination that utilizes a vector to transfer genetic information from one bacterium to another.

Interphase

_________________________ is the period of the cell cycle where the cell grows, performs its normal functions, and prepares for division.

determination

_________________________ is the point during development at which a cell becomes committed to a particular fate due asymmetric segregation of cellular determinants or inductive signalling from neighboring cells.

Cleavage

_________________________ is the process in which a fertilized zygote undergoes rapid cell division at a rate that prevents it from actually growing; a morula is formed in the process.

zona pellucida

_________________________ is the thick transparent membrane surrounding a mammalian ovum before implantation.

Endocytosis

_________________________ is the transport of molecules into a cell through the invagination of the cell membrane and the formation of a vesicle, but is rarely used since it requires a large amount of energy.

generalized transduction

_________________________ is transduction where random bacterial DNA is packaged inside a phage and transferred to a recipient cell

oxidative phosphorylation

_________________________ refers to the combination of the ETC and chemiosmosis; ADP being phosphorylated into ATP due to the oxidation of NADH, FADH2, and the enzymes used in the electron transport chain.

Aerotolerant anaerobes

__________________________ are bacteria that uses fermentation or anaerobic respiration to carry out metabolism. It cannot use oxygen for metabolism, but it is not harmed by the presence of oxygen.

Somatic cells

__________________________ are diploid cells that make up most of the tissue in the body.

Thermophiles

__________________________ are organisms that like to live in environments with extreme temperatures.

ligand-gated ion channel

__________________________ are protein channels that open and close in response to a specific ligand (usually a hormone or neurotransmitter) binding to the allosteric site of the protein.

voltage gated channels

__________________________ are protein channels that open and close in response to changes in membrane potential

Virulence factors

__________________________ are traits found in the plasmids of bacteria that increases pathogenicity.

conjugation

__________________________ is a form of genetic recombination in which genetic material is transferred from a donor bacterium to a recipient bacterium through a conjugation bridge known as a sex pilus.

Incomplete regeneration

__________________________ is regeneration in which lost or damaged tissues are replaced by newly formed tissue that is not identical in structure or function to damaged ones.

Organogenesis

__________________________ is the development and formation of organs in an embryo.

Chemotaxis

__________________________ is the movement of an organism or cell in response to a chemical stimulus.

Envelope

__________________________ is the phospholipid bilayer that surrounds the capsid of a virus. Not all viruses have this structure.

Fertilization

__________________________ is the process of which a sperm fuses with an ovum and release its genetic material to form a zygote.

disjunction/segregation

__________________________ is the separation of homologous chromosomes during anaphase I of meiosis.

Kinetochore

__________________________ is the specialized region on the centromere that links each sister chromatid to the mitotic spindle.

Obligate aerobes

___________________________ are bacteria that require oxygen for metabolism; if oxygen is not present, then these bacteria will die.

Enzyme-linked receptor

___________________________ are membrane receptors where the extracellular portion is the ligand-binding domain, while the extracellular portion is the enzymatic domain.

intercalated discs

___________________________ are specialized connections between myocardial cells containing gap junctions and desmosomes

Totipotent stem cells

___________________________ are stem cells that are able to differentiate into any cell type, both embryonic and placental cells.

Embryonic stem cells

___________________________ are stem cells that are found in the embryo which can develop into any type of body cell

endocrine signaling

___________________________ is a form of cellular communication where the signals involve secreted hormones that travel through the bloodstream to reach a distant target tissue.

Crossing over

___________________________ is a form of genetic recombination in which two homologous chromosomes line up, break off a part of their DNA at the same spot on each chromosome, and exchange the broken piece of DNA with each other.

bacterial genetic recombination

___________________________ is the acquisition of new gene combinations in prokaryotes.

Differentiation

___________________________ is the changing of a cell's structure, function, and biochemistry to match the determined cell type.

osmosis

___________________________ is the movement of water particles from an area of high concentration to an area of low concentration.

Osmosis

___________________________ is the movement of water particles from an area of low solute concentration to an area of high solute concentration.

Centromere

___________________________ is the part of a replicated chromosome that connects the sister chromatids.

Chemiosmosis

___________________________ is the passing of the H+ ions through the special channels in ATP synthase, and then spinning its axle to cause ADP and Pi to form ATP.

specialized transduction

___________________________ is transduction where specific bacterial genes are packaged inside a phage and transferred to a recipient cell

Cytotrophoblast

____________________________ are cells on the interior of the trophoblast that retain their cell boundaries; they line the syncitiotrophoblast to form chorionic villi.

Unipotent stem cells

____________________________ are stem cells that are able to differentiate into only one cell type.

juxtacrine signaling

____________________________ is a form of cellular communication where the signal acts on cells in the local area by directly binding to receptors on adjacent cells.

Apposition

____________________________ is an action in implantation where the trophoblast of the blastocyst comes into direct contact with the endometrial lining of the uterus.

primary active transport

____________________________ is an active transport that directly uses energy from ATP to transport a molecule across the cell membrane.

Complete regeneration

____________________________ is regeneration in which lost or damaged tissues are replaced with identical tissues.

Compotence

____________________________ is the ability of the cells to respond to a growth factor (inducer).

Amnionic cavity

____________________________ is the cavity in the blastocyst that will surround the fetus during development.

osmotic pressure

____________________________ is the hydrostatic pressure required to stop the flow of water from an area of low solute concentration to an area of high solute concentration, the higher it is, the more water will flow to the area of high solute concentration.

embryoblast (inner cell mass)

____________________________ is the inner cell mass of the blastocyst that forms the offspring of an organism.

Active transport

____________________________ is the transport of molecules up their concentration gradient with the usage of energy.

reciprocal induction

____________________________ is when two tissues both induce further differentiation in each other

Facultative anaerobes

_____________________________ are bacteria that can switch between aerobic metabolism (cellular respiration) and anaerobic metabolism (fermentation) depending on the conditions of the bacteria's environment. If oxygen is present, bacteria uses cellular respiration; if oxygen is not present, bacteria uses fermentation.

Scavenger receptors

_____________________________ are immune cell receptors that are used to bind molecules that are produced by bacteria, specifically it binds to the extracellular protein matrix surrounding a bacteria. This allows the immune system to identify the foreign species in the body.

paracrine signaling

_____________________________ is a form of cellular communication where the signal acts on cells in the local area through the diffusion of signals.

Signal transduction

_____________________________ is a series of molecular changes that converts a signal on a target cell's surface to a specific response inside the cell.

Simple diffusion

_____________________________ is the movement of particles down their concentration gradient directly through the phospholipid bilayer.

Phosphorylation

_____________________________ is the transfer of a phosphate group, usually from ATP, to a molecule, to another molecule.

obligate asymmetric replication

______________________________ is replication that a stem cell will undergo, where it divides into a cell that is identical to the original stem cell, and one cell that is differentiated. This allows the stem cell to not be used up when dividing.

Origin of replication

______________________________ is the first part of bacterial DNA to be copied in binary fission.

Cell Migration

______________________________ is the movement of cells in the embryo from their point of origin to their ultimate location, where they can develop into important tissues and organs.

Facilitated diffusion

______________________________ is the movement of particles down their concentration gradient through carrier and channel proteins that permeate the cell membrane.

trophoblast

______________________________ is the outer cell mass of the blastocyst that forms the placenta in an embryo.

Synaptonemal complex

______________________________ is the protein structure that holds homologous pairs together during crossing over.

Passive transport

______________________________ is the transport of molecules down their concentration gradient without using any energy.

Chorion

______________________________ outermost layer of the two membranes surrounding the embryo. Its purpose is to surround the amnion to provide extra protection for the fetus and to help form the placenta during development.

ungated (leak) channels

_______________________________ are protein channels that are always open and allow ions to move along their gradient.

Teratogens

_______________________________ are substances that interfere with development, causing birth defects or even death to a developing embryo.

Kinesin and Dynein

__________________________________ are microtubule-associated motor proteins that function in the rapid transport of materials and organelles within cells.

homologous chromosomes

__________________________________ is a pair of chromosomes in a diploid cell that code for the same thing in an organism.

Positive sense RNA Virus

____________________________________ is a single stranded RNA virus whose genetic material can be directly translated into capsomeres by the ribosomes in the host's cell.

equilibrium potential

________________________________________ is the point at which the movement of ions across the cell membrane is balanced, as the electrostatic pressure pulling ions in one direction is offset by the diffusion force pushing them in the opposite direction. Active transporters are not taken into account here.

ligand

A membrane receptor will activate when it binds to a ________________.

Answer: D. To enzure that the labeled deoxyadenine will be incorporated into the DNA of one of the daughter cells, we have to insert the nucleotide before DNA replication has been completed. Because replication occurs during the S stage, we could introduce the deoxyadenine during G1 or S stage. Because G1 precedes S, the latest point at which the deoxyadenine could be added is the S stage.

A researcher wishes to incorporate a radiolabeled deoxyadenine into the genome of one of the two daughter cells that would arise as a result of mitosis. What is the latest stage of cellular development during which the radiolabeled deoxyadenine could be added to achieve this result? A. G1 B. G2 C. M D. S

About 60-70 cellular divisions

About how many times can a human mitotic cell divide before the cell becomes senescent?

After week 24, the complication rate of the fetus significantly declines, meaning the chances of the fetus's survival increases.

After week 24, do the chances of survival for the fetus increase or decrease?

Cell surface receptors

An immune cell will not initiate phagocytosis unless its _________________________________ successfully binds to the pathogen.

Passive transport Active transport

Any transmembrane transport that is spontaneous and does not require energy (-ΔG) will proceed through ___________________________________. Any transmembrane transport that is nonspontaneous and requires energy (+ΔG) will proceed through ______________________________.

Antibiotics

Archaea are found to be very resistant to ____________________ than bacteria.

Yes, they are always present, but they are always inactive unless they are activated by a cyclin protein.

Are CDKs always present in a cell?

Eukaryotic cells

Are G protein-coupled receptors (GPCR) found in eukaryotic cells or prokaryotic cells?

K+, since there are more K+ leak channels than Na+ leak channels.

Are cell membranes more permeable to K+ ions or Na+ ions at resting potentials?

Embryonic stem cells are. Embryonic stem cells are pluripotent while somatic stem cells are at best multipotent.

Are embryonic stems cells more potent, or are somatic stem cells more potent?

Non-enveloped viruses will persist longer on the surface of objects. The envelope on viruses are very sensitive to heat, detergents, and dessication, meaning enveloped viruses are easier to sterilize/kill than non-enveloped viruses.

Are enveloped or non-enveloped viruses more likely to persist on the surface of objects?

Yes. Since mitotic cells are able to undergo mitosis, it means that they are also ab.e to undergo DNA replication. Since DNA replication leads to shortening of the telomeres, it is possible for mitotic cells to reach replicative senescence.

Are mitotic cells able to reach replicative senescence?

Yes, they can infect humans, such as in the case of hepatitus D.

Are viroids able to infect humans?

Oxygen radicals Nitric oxide Antimicrobal proteins (such as protease or lysozymes) Antimicrobal peptides (such as defensin) Binding proteins (such as lactoferrin)

Aside from lowering the pH inside of itself, what are some other mechanisms that are used to destroy pathogens inside a phagolysosome?

Since glucose is too large and polar to participate in simple diffusion, glucose in the cell is unable to move outside of the cell. In that case, water will flow from outside the cell and into the cell, causing the cell to expand from the increase in concentration of water.

Assuming there are no transport proteins on the cell membrane, if the cell was placed in a hypotonic solution of glucose, what would happen to the cell?

Crystalized

At extremely low temperatures, phospholipids are so cluttered that they become ________________.

Decreases fluidity

At high temperatures, cholesterol ______________ fluidity of a membrane.

Increases fluidity

At low temperatures, cholesterol _____________ fluidity of a membrane.

Week 2 Fertilization occurs two weeks after LMP (last menstrual period)

At what point during gestation does fertilization occur?

Week 3 of gestation

At what point during gestation does gastrulation typically occur?

Nucleoid region

Bacteria do not have a nucleus, so they have their genetic material in a _________________________ in the cytoplasm.

Fimbriae

Bacteria have extracellular structures that are similar to eukaryotic cilia known as _________________.

-Synthesis of proteins destined for the cell membrane

Briefly describe the functions of the following organelle: Rough Endoplasmic Reticulum

-Lipid synthesis -Detoxification

Briefly describe the functions of the following organelle: Smooth Endoplasmic Reticulum

Transduction is the transfer of genetic materials from one bacterium to another through a bacteriophage vector.

Briefly describe transduction.

Transformation is the acquisition of genetic material from outside the cell that can be integrated into the bacterial genome.

Briefly describe transformation.

Connective tissue Epithelial cells Epithelial cells Connective tissue Connective tissue

Classify each of the following cells as epithelial cells or connective tissue: -Fibroblasts, which produce collagen in a number of organs -Endothelial cells, which line blood vessels -α-cells, which produces glucagon in the pancreas -osteoblasts, which produce osteoid, the material that hardens into bone -chondroblasts, which produces cartilage

-Microtubules depolymerize and separates sister chromatids of the chromosomes -Sister chromatids are pulled to the opposite ends of the cell

Describe anaphase II of meiosis II.

Liver: High regenerative capacity Kidney: Moderate regenerative capacity Heart: Little to no regenerative capacity

Describe the regenerative capacity of the following organs in a human: -Liver -Kidneys -Heart

The 9 + 2 arrangement 9 pairs of microtubules surround the center of the structure, with another pair of microtubules in the center. Nexin exists between pairs of microtubules, and dynein comes out of microtubule pairs.

Describe the structure of cilia and flagella.

Consists of 9 triplets of microtubules that surrounds a hollow center.

Describe the structure of the centrioles in the centrosome.

1. Cyclin B protein is produced in the G2 phase. 2. Cyclin B will bind to CDK-1, which will form the CDK-1-cyclin B complex. 3. The complex will activate the process of mitosis by promoting the proteins needed for the process.

Describe what happens at the regulation point of the cell cycle between the G2 phase and mitosis.

Homologous chromosomes

Does crossing over occur between homologous chromosomes or sister chromatids?

Trophoblast Embryoblast

During blastulation, what are the two types of cells that the morula differentiates into?

Mitosis, because cancer cells have a certain defect that causes them to divide more than grow.

During which part of the cell cycle do cancer cells spend most of its life in? Explain why.

Specific

Each channel protein is almost always _______________________ for either a certain molecule or a certain class of molecules.

Tetrad

Each synaptic pair in a synapsis contains 4 chromatids, they are collectively referred to as a _________________________.

Pluripotent, since they can change into any cell type that isn't placental.

Embryonic stem cells are able to differentiate into various cells in order to form an offspring, but they are unable to differentiate into cells that are present in the placenta. What is the potency of the embryonic stem cells?

Catalytic receptors

Enzyme-linked receptors are also known as _____________________________.

One chromosome An individual chromosome

Even when a chromosome has formed two sister chromatids, the whole thing is still considered _________________________. When sister chromatids separate in mitosis, each sister chromatid is referred to as ____________________________.

Gram-negative bacterium

From the image shown, what kind of bacterium would this be?

Answer: B. A rod of mesodermal cells called the notochord develops along the longitudinal axis just under the dorsal layer of the ectoderm. Through inductive effects from the notochord, the overlying ectoderm starts bending inward and forms a groove on the dorsal surface of the embryo. The dorsal ectoderm will eventually pinch off and develop into the spinal cord and brain. While the neural tube forms from the ectoderm, the notochord itself is formed in the mesoderm.

From which of the following layers does the notochord form? A. Ectoderm B. Mesoderm C. Endoderm D. Archenteron

Vm = 61.5 log (P(Na+)*[Na+ out] + P(K+)*[K+ out] + P(Cl-)*[Cl- in]) (P(Na+)*[Na+ in] + P(K+)*[K+ in] + P(Cl-)*[Cl- out]) Vm = 61.5 log ((0.05 * 140 mM) + (1 * 4 mM) + (0 * 12 mM)) ((0.05 * 14 mM) + (1 * 120 mM) + (0 * 120 mM)) Vm = 61.5 log(11 mM/120.7 mM) Vm = 61.5 log(0.09 mM) Vm = 61.5 * (-1.05) Vm = -64.575 mV

Given the data shown, calculate the resting membrane potential of this cell.

compotence

Growth factors only function on specific cell types or in certain areas, which is determined by the cell's _______________________________. This allows growth factors to code for different tissues.

46 23

How about number of individual chromosomes? How many homologous pairs are in a fertilized zygote?

Formed by the cell membrane invaginating itself around the particle in question, which forms a phospholipid bubble around the particle.

How are vesicles formed during endocytosis?

-Cells have repair mechanisms that allows them to repair DNA. -If the DNA damage is irreparable, then p53 proteins will initiate apoptosis to prevent the damaged DNA from being replicated.

How does DNA damage initiate apoptosis?

Typically 9 months (280 days)

How long does gestation typically last?

6

How many connexins are used to make a connexon?

Deuterosomes Protosomes

In ________________________________, the blastopore will develop into the anus, while in ______________________________, the blastopore will develop into the mouth.

Intercalated discs

In cardiac muscle cells, __________________________ permit the passage of ions between cells, allowing an action potential to spread very rapidly to produce a coordinated contraction.

The sperm (male gamete)

In fertilization, which gamete determines the sex of the offspring?

Diploid germ cell Haploid germ cells

In meiosis I, we go from a _________________ cell to two __________________ cells.

Anaphase of mitosis Anaphase I or II of meiosis

In which phase of cellular division can nondisjunction occur in?

gram negative

Is the bacteria shown here Gram-positive or Gram-negative?

gram positive

Is the bacteria shown here Gram-positive or Gram-negative?

Saturated

Is the fatty acid shown here saturated or unsaturated?

Unsaturated

Is the fatty acid shown here saturated or unsaturated?

inner

Is the following a characteristic of the inner mitochondrial membrane or the outer mitochondrial membrane? Contains cristae

Inner,

Is the following a characteristic of the inner mitochondrial membrane or the outer mitochondrial membrane? Contains high levels of cardiolipin and does not contain cholesterol.

inner.

Is the following a characteristic of the inner mitochondrial membrane or the outer mitochondrial membrane? Encloses the mitochondrial matrix, where the citric acid cycle produces high-energy electron carriers used in the electron transport chain.

Outer.

Is the following a characteristic of the inner mitochondrial membrane or the outer mitochondrial membrane? Has many large pores that allows the passage of small ions and small proteins

Allosteric sites

It is possible for a ligand-gated ion channel to have multiple __________________________ on the protein.

Chemosynthetic Photosynthetic

Many Archaea are ____________________________, meaning they are able to generate energy from inorganic compounds, such as sulfur- and nitrogen-based compounds like ammonia. However, there are some Archaea that are __________________________, meaning they are able to generate energy from sunlight.

Reductional division

Meiosis I is an example of ________________________, where homologous chromosomes are separated in cellular division, resulting in haploid daughter cells.

Equational division

Meiosis II and mitosis are an example of ________________________, where sister chromatids are separated without a change in ploidy.

High temperatures

Membrane fluidity is high at _______________ temperatures.

Answer: C. Mitochondria are thought to have evolved from anaerobic prokaryote engulfing an aerobic prokaryote and establishing a symbiotic relationship; therefore, mitochondrial DNA, or mDNA, is likely to be similar to bacterial DNA. Both mDNA and bacterial DNA are organized into a single circular chromosome of double-stranded DNA that can replicate during binary fission. Therefore, Statements I and II are correct, while Statement III is incorrect.

Mitochondrial DNA is: I. circular II. self-replicating III. single-stranded A. I only B. II only C. I and II only D. I, II, and III

Lateral diffusion

Movement of a membrane lipid or protein in the current leaflet of the cell membrane is known as ____________________________. This movement is fast, since it only occurs on one leaflet, and occurs often in the cell membrane. It does not require a catalyst.

Bronchi

Name an example of pseudostratified epithelium.

-Genetics of embryo -Route of exposure -Length of exposure -Rate of placental transmission of teratogens -Type of teratogens -Physiological conditions of mother

Not all teratogens will have the same effect on different embryos. What are factors that determines the effect that teratogens will have on an embryo?

The most advantageous method would be viral extrusion. The other two methods involves the death of the host cell, which would mean it would no longer be used for the reproduction of viruses. Viral extrusion leaves the host cell alive, meaning it can continue to be used for viral replication.

Of the three methods of virions being released from the host, which method is most advantageous for the virus?

They go on to form the umbilical cord.

Once the placenta has developed, what happens to the allatonis and yolk sac?

Viroid & Prion Virus Prokaryotic Cell Eukaryotic Cell

Order the following from smallest to largest: Virus Eukaryotic cell Prokaryotic cell Viroid & Prion

Passive transport Active transport Endocytosis/Exocytosis

Order the following methods of transmembrane transportation from the least amount of energy used to the most amount of energy used: Active transport Endocytosis/Exocytosis Passive transport

Deep within our epidermis, we have stem cells known as epidermal stem cells. These cells constantly divide to provide new skin cells for the epidermis. When old skin cells shed off the skin, the new skin cells made by the epidermal stem cells will move up and take the place of those cells.

Our epidermis is made of epithelial or skin cells that we constantly shed every day. In fact, we shed around 40,000 skin cells per hour. How are we able to keep our skin despite constantly shedding skin cells?

chorion

Part of the structure of _________________________ includes the trophoblast (both the cytotrophoblast and the syncitiotrophoblast) and a somatic mesoderm.

Temperature Temperature

Passive transports such as diffusion, osmosis, and facilitated diffusion will generally increase in rate as _____________________________ increases; likewise passive transport will generally decrease in rate as _____________________ decreases.

One difference is the substance each process takes into the cell. Phagocytosis takes in large solids/molecules like pathogens, pinocytosis takes in small dissolved ions and solutes. Another difference is the specificity of each process. Phagocytosis is very specific based on what binds to the receptors, pinocytosis is not specific.

Phagocytosis and pinocytosis both follow a similar process to one another. How do both processes differ from each other?

Physically touching

Phagocytosis will not occur unless the cell and the particle it wants to engulf are _____________________________.

Low level

Phospholipids in the cell membrane that are clustered together implies a ____________ level of membrane fluidity.

High level

Phospholipids in the cell membrane that are spaced out implies a ______________ level of membrane fluidity.

Secretory pathway

Proteins that are secreted from the cell or become part of the cell membrane follow what is called the _________________________________.

Carbohydrates Phosphates Sulfates

Proteins that are transported to the Golgi apparatus are usually modified by the addition of groups like _________________________, _________________________, and __________________________.

Tyrosine

RTKs are unique in that their enzymatic domain contains _________________.

Phosphates Intracellular proteins phosphorylating

RTKs have the ability to transfer __________________ from ATP to ______________________ through the process of ______________________________ tyrosine.

Answer: A. The spindle apparatus first interacts with the kinetochore fibers near the end of prophase. While the spindle apparatus aligns the chromosomes at the equatorial plate during metaphase, (B), the initial connection of the microtubule to the kinetochore occurs in prophase.

Some studies suggests that in patients with Alzheimer's disease, there is a defect in the way the spindle apparatus attaches to the kinetochore fibers. At which stage of mitotic divisionwould one first expect to be able to visualize this problem? A. Prophase B. Metaphase C. Anaphase D. Telophase

No No Yes Yes

State whether the following forms of transmembrane transportation requires energy: Simple diffusion Facilitated diffusion Primary active transport Secondary active transport

Guanine and cytosine

Telomeres are high in concentration in ________________________ and _______________________________.

Glycerol backbone

The __________________ of a phospholipid consists 3 carbons attached to three hydroxyl groups. It connects the hydrophobic and hydrophilic regions of the phospholipid through ester bonds.

Phospholipid bilayer

The ___________________ is the basic framework of the cellular membrane, consisting of two layers of phospholipids.

Phosphate head group

The ___________________ of a phospholipid consists of four oxygen atoms bound to a phosphorus atom (one oxygen having a double bond). It is considered the hydrophilic region of the phospholipid.

Sex pili

The ______________________ is the conjugation bridge formed by the donor bacteria in conjugation.

Answer: B. The endocytosis (bulk uptake through vesicle formation) of fluid is known as pinocytosis. Phagocytosis, (A), is the endocytotic intake of solids, while exocytosis, (C), is a method of releasing vesicular contents. Drinking, (D), does not apply on a cellular level.

The bulk movement of liquid into a cell through vesicular infoldings is known as: A. Phagocytosis B. Pinocytosis C. Exocytosis D. Drinking

Floppase transbilayer diffusion

The catalyzed movement of a phospholipid from the inner leaflet of the lipid bilayer to the outer leaflet of the bilayer is known as _____________________________. Movement uses a protein called floppase as a catalyst to break down ATP into ADP+P for energy for this movement. Process is considerably faster than without a catalyst.

Flippase transbilayer diffusion

The catalyzed movement of a phospholipid from the outer leaflet of the lipid bilayer to the inner leaflet of the bilayer is known as ______________________________. Movement uses a protein called flippase as a catalyst to break down ATP into ADP+P for energy for this movement. Process is considerably faster than without a catalyst.

The description indicates that the virus contains an outer layer of phospholipids with an inner capsid, meaning it can enter a host via direct fusion. Within the capsid, there is single-stranded RNA that can be immediately translated to proteins by the ribosomes of the host cell.

The coronavirus, which causes the common cold, is described as an enveloped, single-stranded positive-sense RNA virus. What does this indicate about the virus?

Signal sequence

The destination of where certain proteins are heading are determined by a ___________________________.

positive.

The flow of the concentration gradient of Ca(2+) ions into the cell makes the membrane potential more _____________________.

negative.

The flow of the concentration gradient of Cl- ions into the cell makes the membrane potential more _____________________.

Negative

The flow of the concentration gradient of K+ ions out of the cell makes the membrane potential more _____________________.

Answer: D. The influence of a specific group of cells on the differentiation of another group of cells is termed induction. For example. the eyes are formed through reciprocal induction between the brain and the ectoderm. Competence refers to the ability of a cell to respond to a given inducer, but not the influence of the group of organizing cells, eliminating (A). Senescence is a term for biological aging, eliminating (B). Determination may be the result of induction, but this term does not refer to the general concept of the effect of one group of cells on the differentiation of another group of cells, eliminating (C).

The influence of a specific group of cells on the differentiation of another group of cells is called: A. Competence B. Senescence C. Determination D. Induction

Phosphatidyl molecules

The phosphate group of the phospholipid can also bond with certain water soluble moleclues. They bond through the formation of a phosphoester bond from the alcohol functional group of both molecules, which leads to the formation of ____________________ molecules.

hydrophilic (polar) hydrophobic (nonpolar)

The phosphate head group of a phospholipid are considered to be _________________, meaning they like to be around water, while the fatty acid tails of a phospholipid are considered to be ___________________, meaning they rather avoid water.

Entropy (ΔS)

The primary thermodynamic motivator in most passive transports is an increase in __________________________.

-40 mV -80 mV +35 mV

The resting potential of most cells is between ______________ and ____________, although the potential can rise as high as _____________ during depolarization of a cell.

temperature cholesterol presence of saturated/unsaturated fatty acids

The three factors that affect cell membrane fluidity includes ___________________, ______________________, and _____________________.

Donor Recipient

The transfer of genetic material in conjugation flows from the _____________ to the _______________.

Uncatalyzed transbilayer diffusion

The uncatalyzed movement of a phospholipid from the outer leaflet of the lipid bilayer to the inner leaflet of the bilayer, and vice versa is known as ___________________________________. Since no catalyst is used, the movement of the phospholipid is really slow. It does not happen often.

Permeability Transepithelial voltage difference

Tight junctions can limit ________________________ enough to create a _______________________________________________ based on differing concentrations of ions on either side of the epithelium.

Paracellular

Tight junctions prevents solutes from leaking into the space between cells via a ______________________ route.

The yolk sac

Until the placenta has developed, what structure provides nutrients and blood cells for the embryo?

COPI

Vesicle proteins coated in _____________________ are typically sent from the Golgi apparatus to the endoplasmic reticulum.

Sinoatrial node Heart Pacemaker current Voltage Action potential

Voltage-gated non-specific sodium-potassium channels are found in cells of the _______________________ of the _______________________. The channel proteins serve as a _________________________________. As ________________ drops, channels open to bring the cell back to the threshold and fires another ___________________________________.

Proteins that allow cells to recognize each other and contribute to proper cell differentiation and development.

What are cell adhesion molecules (CAMs)?

The type of protein found in gap juntions

What are connexins?

1. The cell is the most basic unit of structure in life 2. All living things are composed of cells 3. All cells come only from preexisting cells 4. Cells carry genetic information in the form of deoxyribonucleic acid (DNA), and this genetic material is passed on from parent to daughter cell.

What are the four tenets of cell theory?

1. Epithelial tissue 2. Connective tissue 3. Muscle tissue 4. Nervous tissue

What are the four types of animal tissues that are made up of eukaryotic cells?

-Autocrine -Paracrine -Juxtacrine -Endocrine

What are the four types of cellular communications?

Centrosomes (Centrioles) Basal Body

What are the two types of microtubule organizing centers (MTOCs) in a eukaryotic cell?

Cells do not respond as well to the presence of insulin, and so do not insert GLUT4 into their membranes. This defect can lead to a drastic increase in blood glucose levels, which can lead to heart disease, stroke, and kidney failure.

What effect does type II diabetes mellitus have on the body?

Eukaryotes have membrane-bound organelles, prokaryotes do not.

What feature distinguishes prokaryotes and eukaryotes?

Problems with growth and differentiation of cells Development of many cancers

What happens if RTKs fail to function?

Unlike the sperm, the ovum has not completed meiosis during fertilization, it is arrested in metaphase II. Once the ovum is fertilized by a sperm, it will finish meiosis II, producing the zygote and a polar body.

What is different about the ovum compared to the sperm during the process of fertilization?

The attachment of a carbohydrate prosthetic group to a protein to form a glycoprotein, which signals for that protein to be transported to the Golgi apparatus.

What is glycosylation.

Apoptosis is mediated by caspases while necrosis is not mediated by caspases.

What is the biggest difference between apoptosis and necrosis?

It is used to propel the sperm in a certain direction.

What is the function of the flagellum in the sperm?

Gives rise to the notochord.

What is the purpose of the axial mesoderm?

Collagen fibers with different minerals like phosphates, magnesium, and calcium.

What makes up hydroxyapatite?

ligand-gated ion channel

What type of membrane receptor is being shown here?

Inducers are often found in the form of growth factors, peptides that promote differentiation and mitosis in certain tissues.

What type of molecule are inducers typically found as?

Small nonpolar molecules Large nonpolar molecules Small polar molecules

What type of molecules are able to undergo simple diffusion?

Large polar molecules Charged ions

What type of molecules are only able to undergo facilitated diffusion?

Connexons

What type of proteins make up a gap junction?

Humans typically exhibit incomplete regeneration, but regeneration capacity varies throughout the different organs in a human.

What type of regeneration do humans typically exhibit?

Symporter It allows glucose to enter the cell up its concentration gradient by also letting sodium to enter the cell as well. Both sodium and glucose are going in the same direction.

What type of secondary active transporter is SGLT2?

Antiporter.

What type of secondary transmembrane transporter protein is being shown here?

Secondary Active Transport

What type of transmembrane transportation is being shown here?

Simple Diffusion

What type of transmembrane transportation is being shown here?

flippase transbilayer diffusion floppase transbilayer diffusion scramblase transbilayer diffusion

What types of membrane movement are being shown here?

Single-stranded RNA Single-stranded DNA Double-stranded RNA Double-stranded DNA

What types of nucleic acid may be present in a virus?

The anus, since humans are deuterosomes

What will the blastopore develop into for humans?

When a somatic cell undergoes a mutation that lets it express telomerase, the cell is able to replicate an unlimited number of times without having the telomeres getting too short. However, cells with this type of mutation can result in the cell dividing uncontrollably, which can lead to the development of cancer.

What would happen if a somatic cell received a mutation that causes it to produce telomerase?

The presence of oxygen will lead to the production of oxygen-containing radicals in these bacteria, which will eventually lead to cell death.

What would happen to an obligate anaerobe if it was placed in an oxygenated environment?

GDP GTP

When a G protein is inactive, it binds to __________________. When a G protein is active, it binds to ___________________.

Enzyme

When a ligand binds to an enzyme-linked receptor, the enzymatic domain functions as a ______________.

Passive Active

When a molecule moves down its concentration gradient, it is participating in __________________ transport. When a molecule moves up its concentration gradient, it is participating in ___________________ transport.

Infected indefinitely Kill the infected cell

When a retrovirus integrates its genetic material into the host's cell genome, it allows the cell to be ____________________________________. Meaning the only way to remove the infection is to ________________________________________.

It is a totipotent stem cell, since it will differentiate into both the trophoblast (placenta) and the embryoblast (embryo).

When an ovum is fertilized by a sperm, it becomes a zygote. The zygote will continually divide to form a mass of cells known as a morula. Once the morula is formed, the cells will differentiate into the trophoblast and the embryoblast to form the blastocyst. What type of potency is the zygote?

SH2 Can

When docking to a fully phosphorylated RTK, proteins must contain a specific domain called _________________, which can bind to phosphorylated tyrosine. Multiple proteins containing this domain (can/cannot) bind to a phosphorylated tyrosine at the same time.

After the last menstrual period (LMP) Birth

When does gestation begin? When does gestation end?

It is considered totipotent until the cells of it have differentiated into the embryoblast and the trophoblast.

When is a zygote considered totipotent?

During blastulation

When is significant growth fist observed in embryonic development?

They are usually found between two layers of epithelial tissue in organs that deal with high levels of stress, like the skin and intestines.

Where are desmosomes typically found in the body?

-Dermis (middle layer of skin) -tendons -ligaments

Where are fibrous connective tissue found in the body?

Found in places where substances need to diffuse from two different places Found in places that needs to resist chemical and mechanical stress

Where are simple epithelium typically found in? Where are stratified epithelium typically found in?

-Between the G1 and S phase -Between the G2 phase and mitosis

Where are the two points of regulation of the cell cycle located at?

In the epithelial lining.

Where are tight junctions typically found in the body?

Takes place in the widest part of the fallopian tube, known as the ampulla.

Where does fertilization take place?

Foreign genetic material typically come from bacteria that has lysed. Its contents are spilled out, which is taken up by bacteria capable of transformation.

Where does genetic information integrated from transformation originate from?

Cytoplasm of the cell

Where does glycolysis take place in?

In the endometrial lining in the uterus.

Where does implantation take place in?

Testes Ovaries

Where does meiosis occur in males? Where does meiosis occur in females?

inner mitochondrial membrane

Where does oxidative phosphorylation take place in?

Mitochondrial matrix.

Where does the Krebs cycle take place in?

On the cell membrane of the bacteria

Where does the electron transport chain occur in bacteria?

In the nucleus In the cytoplasm

Where does transcription take place in? Where does translation take place in?

Found in cells of the intestines.

Where in the body are SGLT2 transport proteins found?

Found on surface of joints Chondrocytes

Where is hyaline cartilage found in the body? What are the cells found in this connective tissue?

Directly next to the nucleus.

Where is the centrosome of the cell located during interphase?

In its capsid.

Where is the genetic material of a virus stored?

Fibers Ground substance

Which characteristics of connective tissue make up the matrix of connective tissue?

The ovum. The ovum contains significantly more mitochondria than the sperm, therefore, the ovum is more often the one that will provide the mitochondria to the offspring.

Which gamete is responsible for supplying the offspring with most of the mitochondria in its cells? Explain your reasoning.

Potassium

Which ion is the most responsible for the membrane potential in a cell?

Answer: C. Every choice describes one of the diverse functions of the Golgi apparatus. It is a crucial organelle for protein trafficking via the secretory pathway. It also serves as one of the first steps of lysosome formation, by organizing lysosomal proteins and making vesicles that will eventually become mature lysosomes. The Golgi is also responsible for various post-translational modifications, including processing of glycosylation. Carbohydrate synthesis also occurs in the Golgi, facilitating glycosylation and other modification pathways.

Which of the following choices describe functions of the Golgi apparatus? I. Post-translational modifications II. Formation of lysosomes III. Carbohydrate synthesis IV. Protein trafficking A. I. and IV. B. II., III., and IV. C. I., II., III., and IV. D. I., II., and III.

Answer: C. The question is asking us to determine the developmental stage with the greatest nuclear-to-cytoplasmic material ratio. During the series of rapid mitotic divisions known as cleavage, the number of cells increases dramatically but the overall volume of the embryo does not change. In fact, the volume of the embryo does not significantly increase until after the blastula has already been implanted. Therefore, a high ratio of nuclear-to-cytoplasmic material will be found at the stage with the greatest number of cells during early development. From the given choices, the stage with the greatest number of cells is the blastula. This is further supported by the fact that the cells are displaced from the center by the blastocoel.

Which of the following developmental stages has the greatest nuclear-to-cytoplasmic ratio? A. Eight-cell embryo B. Morula C. Blastula D. Zygote

Answer: C. Tubulin is the primary protein in microtubules, which are responsible for the structure and movement of the cilia and flagella, eliminating (A) and (B). Centrioles organize microtubules into the mitotic spindle, eliminating (D). Microfilaments are not composed of tubulin, but rather actin, making (C) the correct answer.

Which of the following does not contain tubulin? A. Cilia B. Flagella C. Microfilaments D. Centrioles

Answer: C. Cell membranes are most likely to have a resting membrane potential that is nonzero because the resting membrane potential creates a state that is capable of responding to stimuli. Signalling molecules and channels would not be as useful with a membrane potential of zero. The values given in the answer choices correspond to different stages of the action potential, but the key information is that a resting potential of 0 mV does not maintain gradients for later activity.

Which of the following is LEAST likely to be the resting membrane potential of a cell? A. -70 mV B. -55 mV C. 0 mV D. +35 mV

Answer: C. Plasmodesmata are cell-cell junctions that are found in plants, not animals. Gap junctions, tight junctions, desmosomes, and hemidesmosomes are all found in animals, particularlym in epithelia.

Which of the following is NOT a cell-cell junction in animals? A. Desmosomes B. Gap Junctions C. Plasmodesmata D. Tight Junctions

Answer: D. All trimeric G proteins have α, β, and γ subunits - (A), (B), and (C), respectively. G(s), G(i), and G(q) are subtypes of the G(α) subunit of the trimeric G protein and differ depending on the G protein-coupled receptor's function.

Which of the following is NOT a component of all trimeric G proteins? A. G(α) B. G(β) C. G(γ) D. G(i)

Answer: A. Embryonic stem cells are controversial because they require destruction of the embryo to harvest, eliminating (B). Adult stem cells are significantly less contraversial, but require treatment with various transcription factors in order to increase the level of potency, eliminating (C). Rejection is a concern when foreign cells are introduced into an individual; using one's own stem cells should remove this risk, eliminating (D). Adult stem cells are not naturally pluripotent unless pluripotency has been induced by strategic use of transcription factors. Therefore, (A) is the correct answer.

Which of the following is false with regards to adult stem cells? A. They retain inherent pluripotency if harvested from selected organs. B. They are less controversial than embryonic stem cells. C. They require treatment with various transcription factors. D. There is a reduced risk of rejection if the patient's own stem cells are used.

Answer: C. Some of the main differences between prokaryotes and eukaryotes are that prokaryotes do not have a nucleus, while eukaryotes do, eliminating (B); prokaryotes have ribosomal subunits of 30S and 50S, while eukaryotes have ribosomal subunits of 40S and 60S, eliminating (A); and prokaryotes do not have membrane-bound organelles, whereas eukaryotes do, eliminating (D). The presence of a membrane on the outer surface of the cell could not distinguish a prokaryotic cell from a eukaryotic one because both gram-negative bacteria and animal cells share this feature. Thus, (C) is the correct answer.

Which of the following is not a difference that would allow one to distinguish a prokaryotic and eukaryotic cell? A. Ribosomal subunit weight B. Presence of a nucleus C. Presence of a membrane on the outside surface of the cell D. Presence of membrane-bound organelles

Answer: C. The smooth endoplasmic reticulum is involved in the transport of materials throughout the cell, in lipid synthesis, and in detoxification of drugs and poisons. Proteins from the RER can cross into the SER, where they are secreted into cytoplasmic vesicles and transported to the Golgi apparatus. However, protein synthesis is not a function of the SER, but rather of the free ribosomes or the ribosomes associated with the RER. (C) is therefore the correct answer.

Which of the following is not a function of the smooth endoplasmic reticulum? A. Lipid synthesis B. Poison detoxification C. Protein synthesis D. Transport of proteins

Answer: A. The movement of any solute or water by diffusion or osmosis is dependent only on the concentration gradient of that molecule and on membrane permeability.

Which of the following is true of diffusion and osmosis? A. Diffusion and osmosis rely on the electrochemical gradient of only the compound of interest B. Diffusion and osmosis rely on the electrochemical gradient of all compounds in a cell C. Diffusion and osmosis will proceed in the same direction if there is only one solute D. Diffusion and osmosis cannot occur simultaneously

Answer: D. In prophase, the chromatin condenses into chromosomes, the spindle apparatus forms, and the nucleoli and nuclear membrane disappear. (A) describes anaphase, whereas (B) and (C) describe telophase.

Which of the following is true regarding prophase? A. The chromosomes separate and move to opposite poles of the cell. B. The spindle apparatus disappears. C. The chromosomes uncoil. D. The nucleoli disappears.

Answer: C. After the first cell divisions occur, the embryo consists of a solid ball of cells known as a morula. Then a hollow center forms, creating the blastula. Finally, as the cells begin to differentiate into the three germ layers, the embryo is considered a gastrula. (C) is therefore the correct answer.

Which of the following shows the correct order of early developmental milestones during development? A. Blastula -> gastrula -> morula B. Morula -> gastrula -> blastula C. Morula -> blastula -> gastrula D. Gastrula -> blastula -> morula

Mitochondria

Which organelle is known for initiating apoptosis?

Allatonis

____________________ is an embryonic membrane involved in early fluid exchange between the yolk sac and embryo.

Simple Stratified Pseudostratified

____________________ is epithelial tissue that consists of only one layer. ___________________ is epithelial tissue that consists of two or more layers. _______________________ is epithelial tissue that appear to have multiple layers due to differences in cell height, but are actually one layer.

Zygote

____________________ is the cell that is produced when a male gamete fuses with a female gamete.

Crinophagy

____________________ is the digestion of excess secretory products in the lysosome.

Exocytosis

_____________________ is the process of which cells transport molecules from inside the cell to the outside of the cell.

Subviral particles

_______________________ are molecules that are smaller than viruses and are able to cause infections in organisms. They are categorized as nonliving infectious agents.

Halophiles

_______________________ are organisms that like to live in extremely salty environments.

Somatic stem cells

_______________________ are stem cells that are found in an adult human that are used to repair the body and replenish tissues that need to be replaced.

epithelial tissue

_______________________ are tissues of tightly packed cells that line organs and body cavities

replicative senescence

_________________________ is when the cell reaches senescence because its telomeres became short to the point of possibly risking DNA damage upon further division; thus, the cell is no longer able to divide.

Proteins

__________________________ are not transferred through gap junctions.

Cristae

____________________________ are numerous infoldings of the inner mitochondrial membrane that increases the available surface area for the integral proteins associated with the membrane.

Pluripotent stem cells

____________________________ are stem cells that are able to differentiate into any cell type except for cells found in placental structures.

asymmetric segregation of cellular determinants

________________________________ is the uneven splitting of cellular determinants, like transcription factors, between stem cells, causing one cell to differentiate while the other remains a stem cell.

inductive signalling

________________________________ is when a group of cells induces another group of cells to differentiate through chemical signalling.

Neurotransmitters GABA

_________________________________ act on ligand-gated ion channels at the postsynaptic membrane. The inhibitory neurotransmitter _____________ binds to a chloride channel to open it.

Negative sense RNA Virus

_________________________________ is a single stranded RNA virus whose genetic material must be replicated to synthesize a complimentary RNA strand before it can be translated by ribosomes in the host's cell.