ZOOLONE LE 1 Reviewer
are all interactions beneficial for one/both organisms?
not all interactions are beneficial; for example, a wood rotting mushroom will grow on a a part of the plant causing disease and it is able to take in nutrients from the host
what is the most common type of euploidy?
polyploidy - occurrence of 3 or more sets of chromosomes in an organism (more common in plants than in animals; can be harmful to animals but good for plants)
what is inversion?
portion of a chromosome is reversed
what happens in reverse transcription?
process by which genetic information from RNA gets transcribed into new DNA; can be done through base pairing of single stranded mRNA
autophagy
process wherein lysosomes use enzymes to recycle the cell's own damaged organelles and macromolecules
what comprises the domain bacteria and domain archaea?
prokaryotes
what determines most of the membrane's specific functions?
proteins
what are integral proteins?
proteins embedded in the phospholipid bilayer wherein materials can go inside and outside the cell
what are glycoproteins?
proteins that are covalently bonded to carbohydrates
what are these whole sets of proteins called?
proteomes
what organisms are comprised of eukaryotic cells?
protists, fungi, plants, animals
what is the main electrogenic pump in plants, fungi, and bacteria?
proton pump
what are the nitrogenous bases?
purines - adenine and guanine; larger than pyrimidines because they are composed of 2 fused rings pyrimidines - RNA: cytosine and uracil and DNA: cytosin and thymine; smaller than purines and has a 6-membered ring
what happens to the nitrogenous bases in DNA?
purines base pair with pyrimidines A → T G → C
what is the cis-face of the Golgi apparatus?
receiving side
what is the pentose sugar of RNA?
ribose (1 more oxygen)
DNA and RNA have the same ___ but have different ___
same purines; different pyramidines
what is genetics?
science that deals with heredity
many ____ cells use exocytosis to export their products
secretory
what is a gene?
segment of DNA, a genetic material that encodes a unique protein that makes up an individual
what is the trans-face of the Golgi apparatus?
shipping side
what is the function of ribosomes?
site of protein synthesis
what are the 2 distinct regions of the ER?
smooth ER and rough ER (surface is studded with ribosomes)
what happens when you cross an individual with a dominant factor and a recessive factor?
the offspring will get the dominant trait
what would happen if, during fertilization, the sperm and egg cell contain 46 chromosomes each?
the offspring would have 92 chromosomes and every time the cell divides, the number of chromosomes doubles
what regulates the entry and exit of molecules from the nucleus?
the pores outside of the nucleus (inside the nuclear membrane)
what is positive feedback?
the process is going to hasten/become faster; an end product speeds up its own production ex: when you get a cut, the body detects this and the platelets cascade
what is meiosis I called?
the reduction division
what is a concentration gradient?
the region along which the density of a chemical substance increases or decreases; only talks about 1 solute, even if there are many others present
what is interphase?
the stage between 2 cell divisions
how are the double strands of DNA joined together?
the strands are joined by hydrogen bonding between the bases
what is an example of cotransport?
the sucrose-hydrogen cotransporter; when H+ ions enter the cell, sucrose also passes through to go inside
what is the arrangement of microfilaments?
there are 2 intertwined strands of actin
what are the characteristics of the cilia? in what direction does it move?
there are more of them covering the cell, shorter than the flagella, and they move perpendicular to the swimming pattern (power stroke and recovery stroke)
what is duplication?
there is an extra section of the chromosome that is attached
what are aquaporins?
these are a kind of channel protein that facilities the passage of water
what are chromosome pairs 1-22? what is their role?
these are autosomes; they do not determine sex, they are only involved in the characters of the offspring
what is chromosome pair 23? what is its role?
these are sex chromosomes; they determine the sex of the offspring
what are carrier proteins?
these bind to molecules and change shape to shuttle the substances across the membrane
what are free ribosomes? where are they found?
these create proteins need for function of the cytosol; found in the cytosol
what is the function of attachment proteins?
these maintain the shape and send signals
what are desmosomes?
they are anchoring junctions that fasten the cells together into strong sheets; "stapler"
how are microtubules associated with cell division?
they are associated with the formation of spindle fibers (chromosome movements in cell division)
where are peripheral proteins found?
they are bound to the surface of the membrane and can be found either at the side of the extracellular matrix or in the cytoplasmic side
what are gap junctions?
they are communicating junctions that provide cytoplasmic channels between adjacent cells
what are ribosomes? what are they made of?
they are complexes made of ribosomal RNA and protein
what is the purpose of helical bundles (integral proteins)?
they are for enzymes, transporting, and they are also receptors
what is the purpose of alpha helix integral proteins?
they are for recognition and they are also receptors
what are lysosomes?
they are membranous sacs of hydrolytic enzymes (digestive enzymes) that can digest macromolecules from complex to more simpler forms; "digestive compartments"
most sex-linked traits are linked to what sex chromosome?
they are mostly x-linked (X sex chromosome)
why are organisms open systems?
they are open systems because they are capable of exchanging substances with their environment
what are chromosomes?
they are structures that contain genetic material in the form of DNA (deoxyribonucleic acid)
what are the characteristics of microfilaments?
they are the thinnest
what is the purpose of beta barrel (integral proteins)?
they are transporters, specifically for channel proteins
how do multiple alleles arise?
they arise through mutations at the same gene locus at different times
what do ECM proteins and fibronectins bind to?
they bind to receptor proteins in the plasma membrane called integrins (signaling pathway)
what are homologs? what do they contain?
they contain similar genes encoding the same set of characteristics; the difference is that it holds the alternative of each gene, although they have the same size and shape ex: one of the homologs will be from the purple flower while the other is from the white flower; they cross over during meiosis and genes are switched in the locus
what is the function of microtubules in relation to the cilia and flagella?
they control the beating of the cilia and flagella which are microtubule-containing extensions that project some cells
what is the purpose of the electrochemical gradient and its constituents?
they drive the diffusion of ions across the membrane
what is the function of enzymatic proteins?
they either hasten or slow down a signal; has a lock and key model where it only opens up for certain molecules that are shaped in a specific way
what is the cytoskeleton?
a network of fibers that organizes structures and activities in the cell
what do genes do?
they encode information for building the molecules synthesized within the cell
what is the role of regulatory mechanisms?
they ensure a dynamic balance in living systems
what is the function of transport proteins?
they facilitate movement of molecules through the cell membrane and can change in shape to fit the shape of the molecule since they use ATP
how are microtubules formed?
they grow out from a centrosome near the nucleus
what are the characteristics of intermediate filaments?
they have a hollow tube with lumen; they have fibers with diameters in the middle
what are channel proteins?
they have a hydrophilic channel that certain molecules or ions can use as a tunnel
how are lysosomes made?
hydrolytic enzymes and lysosomal membranes are made by the rough ER and then transferred to the Golgi apparatus for further processing; later on, they become lysosomes
what happens when hydrophilic molecules want to pass through the membrane?
hydrophilic molecules including ions and polar molecules do not cross the membrane easily and enter the cell through transport proteins
what happens when hydrophobic molecules want to pass through the membrane?
hydrophobic (non polar) molecules such as hydrocarbons can dissolve in the lipid bilayer and can pass through the membrane rapidly
study of fish
ichthyology
why does incomplete dominance NOT support the blending theory?
if you self fertilize the F1, there will be one that is red, 2 that is pink, and 1 that is white; red and white still appear so it is not blending theory
what is the importance of mitosis?
important in growth and tissue repair in multicellular organisms
what is Mendel's first law?
in the formation of gametes, paired factors that may specify alternative phenotypes (visible traits) separate so that each gamete receives only one member of the pair ex: Tt → T and t
what is the blending theory of inheritance?
inheritable traits of both parents will blend or fuse to produce offspring of intermediate appearance; both parents contribute equally to a new individual ex: smooth + wrinkly = semi-wrinkly
how does the cytoskeleton aid vesicles?
inside the cell, vesicles can travel along tracks provided by the cytoskeleton
the ____ of the cell is more negative compared to the ____
inside; outside
what are the 2 compartments found in the inner membrane?
inter membrane space and mitochondrial matrix
what type of proteins does the cytoskeleton interact with? why?
interacts with motor proteins to produce motility
what are the different changes that can happen in the chromosome structure?
inversion, deletion, translocation, and duplication
what is the purpose of active transport?
it allows cells to maintain their concentration gradients that differ from their surroundings
what is found inside the nucleus?
it contains most of the cell's genes
what is comprised of the biological membrane in eukaryotic cells?
it has a double layer of phospholipids and other lipids
what does the centrosome contain?
it has a pair of centrioles, each composed of nine sets of triplet microtubules arranged in a ring
what is the nuclear membrane?
it is a double membrane wherein each membrane consists of a lipid bilayer like the plasma membrane
what is feedback?
it is a mechanism wherein cells are able to coordinate various chemical pathways
what is the plasma membrane?
it is a selective barrier that allows sufficient passage of oxygen, nutrients, and waste to service the volume of every cell
what is the electrogenic pump?
it is a transport protein that generates voltage across a membrane
what is facilitated diffusion?
it is a type of passive transport that doesn't use energy
where is the cytoplasm in eukaryotic cells?
it is in the region between the plasma membrane and nucleus
where is the DNA located in the prokaryotic cell?
it is located in the nucleoid which is an unbound region
where is the nucleolus located? what is its function?
it is located within the nucleus and is the site of ribosomal RNA (rRNA) synthesis
where is the DNA located in eukaryotic cells?
it is surrounded by the membranous nuclear envelope
what is the centromere?
it is the constricted region of a chromosome; location of the kinetochore
what is a genome?
it is the entire set of genetic instructions; it is the total genetic material of an organism
what is the cell?
it is the lowest level of organization that can perform all activities required for life
what is feedback regulation?
it is the output/product of a process that regulates that very process ex: if the stimulus is high blood sugar, the body will regulate this through producing insulin; the response will be that glucose will be taken in by the liver and muscle cells (negative feedback)
what is genomics?
it is the study of sets of genes within and between species
what is proteomics?
it is the study of whole sets of proteins encoded by the genome
what is heredity?
it is the transmission of inherited characteristics from parents to offspring
what is the transmission of traits based on?
it is usually based on which traits seen in the previous generation will help in the survival of the organism/group of organisms
what are the internal membranes for in eukaryotic cells?
it partitions the cell into organelles
what is the function of the endomembrane system?
it regulates protein traffic and performs the metabolic functions in the cell
what are the types of cell division?
karyokinesis - division of the nucleus cytokinesis - division of the cytoplasm
what are vacuoles?
large vesicles derived from the ER and Golgi apparatus
how are actin and myosin involved in amoeboid movement?
localized contraction brought about by actin and myosin drives amoeboid movement by extending pseudopodia
what are intermediate filaments made of?
made of several proteins, but the main one is keratin proteins
study of mollusks
malacology
study of mammals
mammalogy
what are multiple alleles? why does this occur?
many dissimilar alleles can exist in a population; occurs because of mutations wherein there are more alternatives to a particular character ex: human ABO blood group
what are vesicles?
membrane enclosed sacs
what is another name for the rough ER?
membrane factory of the cell
what is the cell membrane?
membrane that encloses the entire cell and regulates the passage of materials between the cell and its environment through a semipermeable membrane
what are tight junctions?
membranes of neighboring cells are pressed together, preventing leakage of extracellular fluid inside the cell
what are the types of karyokinesis cell division?
mitosis - division of somatic (body) cells meiosis - division of sex cells/gametes
what are the types of aneuploidy?
monosomy and trisomy
in what type of cell do you find a lot of actin filaments?
muscle cells have thousands of actin filaments arranged parallel to one another
what happens in cell junctions?
neighboring cells in tissues, organs, or organ systems often adhere, interact, and communicate through direct physical contact
reticulum
network
what is incomplete dominance?
no allele is completely dominant over the other ex: red + white = pink
what is translocation?
non homologous chromosomes can exchange sections
what is the function of signal transduction proteins?
they help the signaling processes; lock and key model for the signaling molecule
central vacuoles
they hold organic compounds and water; found in many mature plant cells
where are integral proteins found?
they penetrate the hydrophobic core of the cell membrane
what is the purpose of channel proteins in facilitated diffusion?
they provide corridors that allow a specific molecule/ions to cross the membrane; has a tunnel in between where the substances can pass and can open, close, or change in shape
contractile vacuoles
they pump the excess water out of cells; found in many freshwater protists
how do cells recognize each other?
they recognize each other by binding to molecules, often containing carbohydrates, on the extracellular surface of the plasma membrane
what is the purpose of carrier proteins in facilitated diffusion?
they undergo a subtle change in shape that translocates the solute-binding site across the membrane
what happens if heterozygous individuals have a dominant allele?
they will have the same phenotype as the homozygous dominant individuals, meaning that the heterozygous individual will still portray the dominant trait and not the recessive
where do lysosomal enzymes work best in?
they work best in the acidic environment inside the lysosome; pH of 5
what is the function of the mitochondria?
this is the site of cellular respiration
what happens in S?
this is where chromosomes and DNA will replicated and identical structures called sister chromatids are formed
what are emergent properties?
those that arise through interactions among smaller parts that alone do not exhibit these properties while a level is arising, there are new properties that appear that were not present in the previous level once these individual components come together, there is an emergent property that they have for them to reach the next level ex: the individual components of a bicycle are useless until you put them all together; only then is it a fully functioning bicycle
how do you determine the genotype?
through a test cross which is crossing an individual of unknown genotype with a homozygous recessive individual
why are interactions between the components of a system important?
to ensure the smooth integration of all the parts; an organism by itself will not be able to live alone because it needs other components of the system it belongs to in order to survive
what is the purpose of the cristae?
to present a large surface area for enzymes that synthesize ATP
what is sex-linked inheritance?
traits specified by genes located on sex chromosomes
what type of proteins are used in facilitated diffusion? why is this used?
transport proteins that speed the passive movement of molecules across the membrane
what happens in exocytosis?
transport vesicles migrate to the membrane, fuse with it, and release their contents outside the cell
what is the legend for homozygous recessive?
tt (all lower case)
what are the characteristics of microtubules?
tubular, has a hollow tube, thickest
what is the difference between unicellular and multicellular?
unicellular - has the ability to survive, take in food, and reproduce by itself; also has the ability to remove substances from its body (excretion) and maintain itself to survive in its own environment (homeostasis) multicellular - requires a group of cells working together for them to survive
what occurs in active transport?
uses ATP energy to move the solutes against their concentration gradient; low to high concentration
what is aneuploidy?
usually caused by failure of a pair of homologous chromosomes to separate during meiosis (nondisjunction)
what are the characteristics of the flagella? in what direction does it move?
usually only 1 or 2 in the cell, longer than the cilia, and have parallel movement to the swimming pattern
the components of the endomembrane system are either continuous or connected via transfer by ___
vesicles
what is membrane potential?
voltage difference across a membrane
what causes voltage in the cell?
voltage is created by the differences in the distribution of positive and negative ions across the membrane
what is surrounding the nucleolus?
what is surrounding the nucleolus?
what is bulk transport?
when large molecules like polysaccharides and proteins cross the membrane in bulk via vesicles; requires ATP
what is phagocytosis?
when the cell engulfs a particle by wrapping pseudopodia (phosphate) around it and packaging it within a membrane-enclosed sac; "cellular eating"
what is pinocytosis?
when the cell gulps droplets of extracellular fluid from the outside to the inside by means of tiny vesicles, whatever molecules or ions that are in the extracellular fluid will also be placed inside the cell; "cellular drinking"
what is endocytosis?
when the cell takes in macromolecules by forming vesicles from the plasma membrane
what is a hypertonic solution?
when the solute concentration is higher outside than inside the cell and the cell loses water (shrivels)
what is an isotonic solution?
when the solute concentration outside is the same as the inside and there is no net water movement
what is a hypotonic solution?
when the solute concentration outside the cell is less than inside the cell and the cell gains water (lyses)
endoplasmic
within the cytoplasm
does the eukaryotic cell have a nuclear envelope? does it have membrane enclosed organelles?
yes, it is double layered; yes
what is a monohybrid cross?
a cross involving only a single locus in the chromosome (only looking at one character with 2 contrasting traits); involves variation at a single locus
what is negative feedback?
a loop in which the response reduces the initial stimulus
what is cellular respiration?
a metabolic process that uses oxygen to generate ATP
what happens in telophase I?
- 2 daughter cells are formed with each daughter cell containing only 1 chromosome of each homologous pair - 1 cell becomes 2 with haploid set of chromosomes
what are the functions of peripheral proteins?
- can be enzymes - can serve as anchorage - can be transporters/carriers
what happens in telophase II?
- cell division is complete - 4 haploid daughter cells are formed, each with half the number of chromosomes as the parent cell - each gamete has a haploid number of chromosomes, all in the unduplicated state
what happens in telophase?
- chromosomes complete migration to opposite poles - spindle fibers disappear - chromosomes condense and become fibers again - nuclear membrane and nucleolus will reappear
what happens in prophase I?
- each chromosome duplicates itself and the resulting chromosomes called sister chromatids remain closely associated - instead of just the sister chromatids, there is a homologous pair of chromosomes (maternal and paternal) - the duplicated chromosomes pair with their homologous chromosomes in a process called synapsis - there is a crossing over between homologous chromosomes and this causes the recombination of genes
what happens in anaphase I?
- each of the homologous pair separates from its partner and the 2 move toward opposite poles - each of the homologous pairs are going to become half of the original number of chromosomes (haploid)
what is Mendel's second law?
- genes that are located on different pairs of homologous chromosomes will assort independently during meiosis - pertains to studies of 2 pairs of hereditary factors at the same time (length of stem and color of seeds) - ex: genes for tall and genes for yellow are not found on the same kind of homologous chromosomes; either on different loci or diff homologous chromosomes
what are the functions of intermediate filaments?
- maintain cell shape (they are tension bearing elements) - holds up/anchors the nucleus and other organelles to stay in the cell - they are for the formation of the nuclear lamina
what happens in prophase II?
- no DNA replication unlike prophase I - sister chromatids of each chromosome are still attached at the centromere
what is the difference between plant and animal cells? (animal)
- nucleus in animal cells is in the middle - have a flagella/cilia that enables them to become mobile - have no central vacuole; instead, they have smaller vacuoles found in the periphery of the cell - don't have a cell wall, only a cell membrane
what are chromosomal aberrations?
- structural and numerical deviations form the norm that affect many genes at once - some types of chromosomal aberrations are due to changes in the number of chromosomes
what are the functions of the smooth ER?
- synthesizes lipids and steroids - metabolizes carbohydrates - detoxifies drugs and poisons - stores calcium ions
how is DNA converted into protein?
- the DNA is able to self replicate, it undergoes the transcription process where the mRNA is transcribed from the information of the DNA - the single stranded mRNA will leave the area of the nucleus towards the area of the cytoplasm; when it reaches this, it will go to the area of the ribosomes where it will stay in the area of the rRNA and ribosome proteins - mRNA will be translated into a particular amino acid; they will bind together to form the proteins or the polypeptides
what happens in prophase?
- the centrosomes (which contain the centrioles) replicate and migrate to opposite poles - the nuclear membrane is slowly disassembled and nucleolus disappears - spindle fibers are formed and are going to radiate from the area of the centrioles; will become longer as they reach the area of the poles - chromatin fibers condense and are now seen as chromosomes where you can see the sister chromatids
what happens in cytokinesis?
- the cleavage furrow will form - myosin and actin filaments will contract (contractal ring) and will cleave the cell in 2, forming 2 daughter cells with the exact same genetic material as the parent cell
what happens in anaphase?
- the cohesion proteins holding the sister chromatids together are removed and detached - chromosomes are being moved towards opposite sides of the cell and the spindle fibers are getting shorter - the sister chromosomes become independent chromosomes; each side of the cell still has the exact same number of chromosomes that the parent cell had
what happens in interphase, apart from the 3 stages?
- the nucleolus is seen under the microscope - chromosomes are not seen under the microscope since they are still chromatin fibers - centrosomes with a pair of centrioles
what happens in metaphase?
- the pairs of centrioles are now on opposite poles - the centromere region of each chromosome is equipped with 2 kinetochores which are the attachment points for the spindle fibers - the spindle fibers have pulled the chromosomes to the metaphase plate
what are the functions of the rough ER?
- the rough ER has bound ribosomes which secrete glycoproteins (protein synthesis) which are distributed through transport vesicles - manufactures membranes
what are the functions of the Golgi apparatus?
- the transport vesicles coming from the rough ER are received by the Golgi apparatus - modifies products of the ER - manufactures certain macromolecules - sorts and packages materials into transport vesicles
what are the 5 characteristics of all animals?
- they are heterotrophs; they are unable to make their own food and instead they ingest it - require oxygen in their blood to survive - reproduce sexually ad sometimes asexually - usually motile during some part of their life - able to go through embryonic development
what are the cilia and flagella made of?
- they are made up of a core of microtubules sheathed/covered by the plasma membrane - has a basal body that anchors the cilium/flagellum and has a 9 x 3 arrangement
what is the function of microfilaments?
- they maintain cell shape (they are tension bearing elements) - can help the cell change shape - muscle contraction - cytoplasmic streaming in plant cells; there are certain ways by which plant cells are able to communicate and transfer substances from one cell to another - cell motility - involved in the division of animal cells
what is the function of microtubules?
- they maintain cell shape because they are compression-resisting girders - cell motility because they are associated with the cilia and flagella - organelle movements
what happens in G1?
- this is the preparatory stage for DNA replication where the cell will synthesize the things that it needs for cell division such as tRNA, ribosomes, mRNA, and enzymes - this is the part that is involved in the growth and development of the cell
what happens in G2?
- this is where the synthesis of spindle fibers and aster proteins occur, of which are found in the area of the centrioles - this is where the synthesis of organelles (such as centrioles) occurs
what are the functions of the cytoskeleton?
- to organize the cell's structures and activities, anchoring many organelles - has the ability to move, making the cell moveable - helps to support the cell and maintain its shape
how many homologous pairs does each daughter cell receive?
1
what is trisomy?
1 extra chromosome that is relative t the diploid parental number
what is monosomy?
1 less chromosome relative to the diploid parental number
what are the 3 types of RNA?
1. messenger (mRNA) - carries a copy of a message transcribed on DNA out of the nucleus and into the cytoplasm (mRNA is made in the nucleolus) 2. transfer RNA (tRNA) - carries the individual amino acids to the sites of protein synthesis (protein synthesis happens in the area of ribosomes) 3. ribosomal RNA (rRNA) - along with proteins, makes up the ribosome; holds mRNA and tRNA molecules in just the right position to make polypeptides
what are the 4 basic features found in all cells?
1. plasma membrane 2. cytosol (semi-fluid substance) 3. chromosomes (carry genes) 4. ribosomes (make proteins)
what happens in oogenesis?
1. the oogonium is diploid and will undergo mitotic division through the multiplication phase; will become 2 diploid primary oocytes 2. the primary oocytes will undergo meiosis I wherein reduction of chromosomes will occur such that a haploid set is produced, which are the secondary oocytes 3. there is unequal division between the 2 secondary oocytes; one becomes a polar body 4. the secondary oocytes will undergo meiosis II wherein there is no more reduction of chromosomes (still haploid) and will become ootids 5. the secondary polar body is formed 6. all polar bodies disappear and the ootid becomes an ovum
what happens in spermatogenesis?
1. the spermatogonium which has a diploid number of chromosomes (46) will undergo a multiplication phase; this happens in the area of the testes 2. the spermatogonium will undergo mitotic division, forming 2 primary spermatocytes with diploid chromosomes 3. the primary spermatocytes will undergo meiosis I wherein the diploid chromosomes become haploid (half) and will then become secondary spermatocytes 4. the secondary spermatocytes will undergo meiosis II and will divide, becoming spermatids; there is no more reduction of chromosomes and will retain a haploid number for each of the spermatids 5. the spermatids will undergo cell differentiation, the tails appear, and they will become sperm
what are the 6 types of integral proteins?
1. transport proteins 2. enzymatic proteins 3. signal transduction proteins 4. recognition proteins 5. joining proteins (intercellular joining) 6. attachment proteins
in DNA, how many base pairs occur per turn?
10
how many daughter cells does one parental cell produce? how many chromosomes are in each of these daughter cells?
2 daughter cells (diploid); 46 chromosomes diploid → diploid
how many hydrogen bonds are between A and T?
2 hydrogen bonds
how many membranes does the mitochondria have?
2; has a smooth outer membrane and an inner membrane folded into cristae
how many hydrogen bonds are between G and C?
3 hydrogen bonds
what is the cytoskeleton composed of?
3 molecular structures: microtubules, microfilaments, and intermediate filaments
what are the 2 kinds of nucleic acids that a cell has?
DNA and RNA
who is the father of genetics?
Gregor johann Mendel
what are the stages in interphase?
G1, S, G2
what blood types are equally dominant? what happens when you cross this?
I^A and I^B are equally dominant; when you cross this you get AB
what is the legend for homozygous dominant?
TT (all capital)
what is the legend for heterozygous?
Tt (one uppercase one lowercase)
what are the sex chromosomes of females?
XX
what are the sex chromosomes of males?
XY
what is tonicity?
ability of a surrounding solution to cause a cell to gain or lose water
how much space does the endoplasmic reticulum account for?
accounts for more than half of the total membrane in many eukaryotic cells
what are microfilaments made of?
actin filaments (protein) and myosin
what is euploidy?
addition or deletion of whole sets of chromosomes
what comprises the domain eukarya?
all eukaryotic organisms and includes three multicellular kingdoms: 1. plants, which produce their own food by photosynthesis 2. fungi, which absorb nutrients through decomposition 3. animals, which ingest their food
how do organisms maintain homeostasis in terms of interacting with the environment?
all organisms are able to sense and respond to stimuli in order to maintain homeostasis
what are microtubules made of?
alpha and beta tubulin
what are alleles?
alternate forms of a gene for the same trait (dominant and recessive; T, t)
study of spiders
arachnology
what is dynamic equilibrium?
as many molecules cross the membrane in one direction as in the other
what are the 3 domains of life?
bacteria, archaea, and eukarya
why is the plasma membrane part of the endomembrane system?
because of the fact that this is also a double membrane, they basically come from the same complex
what is systems biology?
biologists use this to explore emergent properties and analyze the interactions among the parts of a biological system doesn't analyze merely one organism, it studies everything surrounding that one system
what is codominance?
both traits are expressed at the same time ex: white + brown = white with brown spots
in prokaryotic cells, what surrounds the cell apart from the cell wall? what is the purpose of this?
capsule; it serves as a form of protection and a way for them to adhere to surfaces
the plasma membrane also contains ___ side chains
carbohydrate
what is the function of joining proteins?
cells that are tightly packed together can join using these proteins
what happens in anaphase II?
centrosomes divide and the sister chromatids of each duplicated chromosome will migrate separately towards opposite poles, becoming full chromosomes each with a set of haploid chromosomes
what is comprised of the electrochemical gradient?
chemical force - the ion's concentration gradient electrical force - effect of the membrane potential on the ion's movement
what happens to the chromatin in preparation for cell division?
chromatin condenses to form discrete chromosomes
what consists of the Golgi apparatus?
consists of flattened membrane sacs calles cisternae
what is osmoregulation?
control of solute concentrations and water balance
what is the pentose sugar of DNA?
deoxyribose (1 less Oxygen)
what is osmosis?
diffusion of water molecules across a selectively permeable membrane
what domain/s comprises of prokaryotic cells?
domain bacteria and domain archaea
everything in the endomembrane system is composed of ____ membranes
double
what protein is found in the cilia/flagella? what is its purpose?
dynein (motor protein) which drives the bending movements
what happens in metaphase II?
each of the duplicated chromosomes align at the equatorial plate
what are the other functions of the plasma membrane?
enables the cell to communicate with other cells serves as a signal pathway for molecules that are going to reach the membrane
what is deletion?
entire blocks of the gene are lost
study of insects
entomology
since animal cells lack cell walls, what covers the cell?
extracellular matrix
what is a chromatin?
fibers made of DNA and protein
what is the arrangement of intermediate filaments?
fibrous proteins are coiled into cables
food vacuoles
formed by phagocytosis
what is meiosis II called?
gamete formation
what is the unit of inheritance?
genes
what is the function of recognition proteins?
glycoproteins enable the cell to communicate with other cells similar to them
what is the extracellular matrix composed of?
glycoproteins such as collagen, proteoglycans, and fibronectin
study of reptiles and amphibians
herpetology
sex chromosomes X and Y are ____
heteromorphic - sex chromosomes X and Y are different in size and shape and also do not contain the same linear sequence of genes; all pairs of autosomes are same in size and shape
what happens in metaphase I?
homologous pairs of chromosomes will align at the equatorial plate
by how much does nuclear division occupy in the cell cycle?
nuclear division occupies 5-10% of the cell cycle and the remainder of the cell's time is spent in interphase
what consists of the endomembrane system?
nuclear envelope, ER, Golgi apparatus, lysosomes, vacuoles, plasma membrane
the ER is continuous with the ____; why is this so?
nuclear envelope; when RNA is released by the pores of the nuclear envelope, it directly goes to the ER
DNA and RNA are both polymers of ___
nucleotides
what is the difference between plant and animal cells? (plant)
nucleus in plant cells are peripheral
what are the organelles that prokaryotic cells do not possess?
nucleus, nuclear membrane, double membrane, no membrane bound organelles
how does bulk transport occur?
occurs by exocytosis and endocytosis
what is cotransport?
occurs when active transport of 1 solute indirectly drives the transport of other substances; instead of just 1 solute going through 1 protein, it is also going to allow the movement of other/more molecules to go inside the protein as well
what is receptor mediated endocytosis?
on the membrane, solutes bind to receptor proteins wherein these proteins cluster in coated pits and each pit forms a vesicles containing the bound molecules
where are bound ribosomes found?
on the outside of the ER (on the rough ER specifically)
what do the hydrophobic regions of the integral protein consist of?
one or more stretches of non polar amino acids which are often coiled into alpha helices
what organisms need osmoregulation? why
organisms that lack cell walls need to have adaptations like osmoregulation when they are exposed to hypertonic or hypotonic environments; a cell without rigid cell walls cannot tolerate excessive uptake nor excessive loss of water
study of birds
ornithology
chromosomes usually occur in ____; where do these come from?
pairs/homologs; one pair is maternal and the other is paternal
what is a nucleotide composed of?
pentose sugar (5 carbon sugar), nitrogenous base, and a phosphate group
what is the cell wall made of in prokaryotic cells?
peptidoglycan which is a combination of protein and carbohydrates
what are the three types of endocytosis?
phagocytosis, pinocytosis, and receptor mediated endocytosis
what is the major electrogenic pump found in animal cells?
sodium potassium pump
what happens in the mitochondrial matrix?
some metabolic steps of cellular respiration are catalyzed
how do lysosomes digest molecules?
some types of cells can engulf another cell by means of phagocytosis and this forms a food vacuole; a lysosome fuses with the food vacuole and digests the molecules
what are these different groups in taxonomy?
species → genus → family → order → class → phylum → kingdom → domain
why is receptor mediated endocytosis specific?
specific because of the receptors found on the cell membrane wherein only ligands can bind to it
where do spindle fibers come from? what are they made of?
spindle fibers come from the centrioles and are made up of microtubules
what is homeostasis?
state of internal balance
transport proteins are always ____ for the substance it moves
substrate specific
in what direction does DNA synthesis occur?
synthesis occurs in the 5' to 3' direction in both strands; the DNA strands are antiparallel
what is diffusion?
tendency for molecules to spread out evenly into the available space; movement of molecules fro a high to a low concentration
the phosphate group of a nucleotide is always attached to ___
the 5th carbon (5')
what happens in transcription?
the DNA sequence of a gene is copied to make an RNA molecule
what happens in translation?
the RNA sequence is translated into a sequence of amnio acids as the protein is formed
what is the arrangement of microtubules?
the arrangement contains column of tubulin dimers
how is the distribution of proteins, lipids, and carbohydrates in the plasma membrane determined?
the asymmetrical distribution of these is determined when the membrane is built by the rough ER and the Golgi apparatus
what is taxonomy?
the branch of biology that names and classifies species into groups of increasing breadth
what is the concept that scientifically explains the unity and diversity of organisms?
the concept that living organisms are modified descendants of common ancestors
what is passive transport?
the diffusion of a substance across a membrane with no energy investment; substances diffuse down their concentration gradient
what is the kinetochore?
the disk of proteins that bind with spindle fibers
what happens if a female has one X sex chromosome that contains a sex-linked trait, but the other sex chromosome does not?
the female will only be a carrier of the disease; the trait will only show if both X sex chromosomes contain the sex-linked trait
nitrogenous base of a nucleotide is always attached to ___
the first carbon (1')
what is the relationship between structure and function?
the form of a structure will always definitely fit its function ex: you don't use a screwdriver for nails, a particular tool is for a particular function ; sodium-potassium pump
what is the chromosomal theory of inheritance?
the idea that Mendel's hereditary factors (genes) are located on the chromosome (studied by Walter Sutton and Theodor Boveri)
what happens if a male has one X sex chromosome that contains a sex-linked trait, but the other Y sex chromosome does not?
the male will show the sex-linked trait
what surrounds the nucleus? what is its function?
the nuclear envelope encloses the nucleus; it separates it from the cytoplasm and other organelles in the cell