Chapters 3,4, &5

If we inspect most cell membranes in a living human body, we would find a nearly continuous flow of substances back and forth across the plasma membrane. Which of the following explains this continuous flow?

A) Cell metabolism is constantly using up oxygen and raw materials; this lowers their concentration, so more will diffuse into the cell.

Which of the following are functions of the plasma membrane? Select all that apply.

A) It separates the internal environment of the cell from the external environment. B) It regulates the entrance and exit of molecules to and from the cell. C) It helps the cell and the organism maintain a steady internal environment.

What evidence suggests that proteins are synthesized and modified in the rough ER as opposed to the smooth ER?

A) Ribosomes are associated with the surface of the rough ER.

What is the difference between the chromosomes in a secondary spermatocyte and those in a spermatid?

A) The chromosomes in secondary spermatocytes consist of two chromatids; the ones in the spermatid consist of only one chromatid.

How can marine animals such as sharks live in a salt water?

A) They increase or decrease the amount of urea in their blood until the blood is isotonic with the environment.

Which of the following proteins would you expect to be a coded for by a proto-oncogene?

A) a growth factor receptor

Oxygen diffuses into the capillaries of the lungs because there is

A) a higher concentration of O2 in the alveoli than the capillaries.

In certain cancerous cells, the cell divides continuously even in the absence of a growth factor (signaling molecule) that indicates the cell should divide. Which of the following could explain this?

A) a receptor molecule that is always turned on

Which cell junctions are commonly found in areas that are subject to stretching, such as the skin?

A) adhesion junctions

Which component of the extracellular matrix is responsible for forming proteoglycans?

A) amino sugars

Which of the following cells were most likely the first type of cells on Earth?

A) bacteria

Which of the following events would be controlled by an external signal?

A) cell division

Which type of cells will have modifications that increase the surface-area-to-volume ratio?

A) cells that specialize in absorption

In plant cells, what is responsible for organizing the spindle?

A) centrosomes

The nucleolus

A) contains RNA and is found in the nucleus.

When does apoptosis occur?

A) during development

Which intercellular junction allows for the rapid movement of small molecules or ions to flow from one animal cell to the next?

A) gap junctions

The second meiotic division is essentially a mitotic division except for the fact that the cells produced are

A) haploid

Two solutions are separated by a selectively permeable membrane. On side A, there is a solution composed of 20% protein and 80% water. On side B, the solution is 100% water. Initially, the solution on side B is ____to the solution on side A.

A) hypotonic

Which of the following factors could cause the cell membrane to become less permeable?

A) if the channel proteins were to denature and become inactive

Receptor-mediated endocytosis

A) involves receptor proteins binding to specific molecules.

Which of the following would be considered evidence that chloroplasts are involved in photosynthesis?

A) isolated chloroplasts give off oxygen when exposed to sunlight.

Compared with a eukaryotic cell, a prokaryotic cell

A) lacks organelles beyond ribosomes.

Tay-Sachs is a serious childhood metabolic disorder where ____ fail to digest certain lipids.

A) lysosomes

Kinesin and dynein are associated with

A) microtubules.

The cell cycle consists of

A) mitosis and interphase

In a person with a disease in which the mitochondria do not produce enough energy for the cell, which organs would be the most severely affected?

A) muscles

Ribosomal RNA is produced in the

A) nucleolus

The pressure that is generated when water flows through a differentially permeable membrane is termed

A) osmotic pressure

When an intestinal cell ingests substances inside very small vesicles that can only be seen with an electron microscope, this is

A) pinocytosis

Which structure regulates passage of molecules into and out of the bacterial cell?

A) plasma membrane

A compound would make a good antibiotic if it affects a structure or process only found in bacterial cells and not in our eukaryotic cells. Which of the following actions would theoretically make a good antibiotic?

A) prevents repair of the peptidoglycan cell wall

You are examining a cell under the microscope and see what appear to be four sister chromatids bound together and remnants of the nuclear envelope. What stage of meiosis are you looking at?

A) prophase I

What two components are commonly found in the extracellular matrix that help resist stretching and provide resilience?

A) proteins and polysaccharides

Proteins that promote the cell cycle and prevent apoptosis are encoded by

A) proto-oncogenes

If the total number of chromosomes in a cell is six, then after mitosis there will be

A) six chromosomes in each daughter cell

If the proteins forming the cell junctions within the stomach were denatured, what is a likely consequence?

A) the desmosome junctions would not hold together, causing the cells in the stomach to pull apart.

If the mitochondrion is the result of endosymbiosis, what membrane of the mitochondrion represents the engulfing vesicle?

A) the outer mitochondrial membrane

The Golgi apparatus directs its protein products to the correct location in the cell based on

A) the specific molecule that is added and the molecule determines the destination in or out of the cell.

Which of the following would be a way of finishing this hypothesis about the function of the Golgi apparatus? If the Golgi apparatus is involved in packaging products for secretion, then

A) vesicles must travel from the Golgi to the cell surface.

In the Malpighian tubules of an insect (blind, threadlike excretory tubule attached to the gut of an insect), salt molecules are actively transferred from body fluids to the inside of the tubule. This transfer of salt molecules would result in

A) water being "pulled" by osmosis into Malpighian tubule.

A cell placed in a hypotonic solution will

B -Gain water

Meiosis results in a change in chromosome number indicated by

B) 2n to n

In humans, the diploid number of chromosomes is

B) 46

If the diploid chromosome number is 16, the chromosome number of each gamete will be

B) 8

Which of the following is true concerning the cell theory?

B) Anton van Leeuwenhoek is recognized for making some of the earliest microscopes.

Which is true of facilitated transport by carrier proteins?

B) It is represented by the glucose carrier that can transport hundreds of molecules a second.

Brock's father has inherited a mitochondrial disease. Is Brock in danger of also having this disease? True or False?

B) No (mother to child)

A cell is placed in a solution of large carbohydrate molecules tagged with a red dye. Soon the cell is dark red, showing a concentration of the nutrient much higher than the external solution. We add a reagent that blocks the use of ATP. What result would you expect from this experiment?

B) The color will remain the same since all future transfer will stop.

Which is a correct example of tonicity?

B) Turgor pressure is created when a plant cell swells in a hypotonic solution.

A semipermeable membrane sac filled with water and large molecules of starch is suspended in a beaker of distilled water. What will happen?

B) Water will enter the sac and it will swell.

When you cut into most active plant tissue, water appears almost immediately because plant cells contain

B) a hypotonic solution that produces turgor pressure.

What forms the contractile ring in animal cells?

B) actin filaments

During what stage do homologous chromosomes seperate from each other?

B) anaphase I

During what stage of meiosis do sister chromatids separate from each other?

B) anaphase II

Which of the following is a function of the cytoskeleton?

B) anchors organelles in place within a cell

Centrioles

B) are short cylinders of microtubules surrounding a hollow center.

You are investigating a cell under the microscope and you realize the cell is missing ribosomes. Based on what you know about ribosomes, the cell would

B) be unable to synthesize proteins.

Which of the following structure(s) is/are only found in a plant cell?

B) chloroplast

Which of the following molecules add stiffness and strength to the plasma membrane?

B) cholesterol

Which organelles have a 9+2 pattern of microtubules?

B) cilia and flagella

The definition of osmosis is the

B) diffusion of water across a selectively permeable membrane

Which of the following refers to materials only leaving the cell?

B) exocytosis

Microtubules

B) form a spindle that distributes chromosomes in an orderly manner.

Which organelle has 13 rows of tubulin dimers around an empty central core?

B) microtubules

The "powerhouse" of the cell is the

B) mitochondrion

The mitotic stage of cell division consists of

B) mitosis and cytokinesis

if a selectively permeable membrane separates a molasses solution from distilled water, over time the

B) molasses will become more dilute

Which of the following is the largest eukaryotic organelle?

B) nucleus

During what stage of mitosis does the nuclear envelope disappear and the chromosomes become distinct?

B) prophase

If an active cell produces an important protein for secretion, what is the correct sequence of organelles that are involved in the production of the protein?

B) ribosomes-endoplasmic reticulum-Golgi apparatus

Osmosis can occur when a membrane is

B) selectively permeable

Which of the following are genetically identical?

B) sister chromatids

If a cell lacks ATP, which of the following processes would cease to operate immediately?

B) sodium/potassium pump

In some bacteria, the outermost layer is a gelatinous sheath known as

B) the capsule.

When water enters a plant cell

B) the central vacuole becomes enlarged.

Permeability refers to

B) the extent to which a membrane allows a substance to pass through.

If the chloroplast is the result of endosymbiosis, which membrane of the chloroplast represents the plasma membrane of the original prokaryote?

B) the inner chloroplast membrane

Certain individuals with a Y chromosome develop into females because testosterone is unable to induce the formation of male sexual characteristics. This is most likely due to a defect in

B) the receptor.

Which of the following is true of the chromosomes in a cell undergoing mitosis?

B) they are unavailable for RNA synthesis

If a crayfish has 200 total chromosomes in its body cells (not ovaries or testes)

B) they would consist of 100 pairs with one of each pair from the father, one of each pair from the mother

If 0.9% NaCl were isotonic to a cell, then

C) 1.0% would be hypertonic to the cell

Which cellular structure is responsible for packaging materials within the cell?

C) Golgi apparatus

Which of the following best describes the role of histones?

C) Histones are responsible for packaging the DNA so it can fit into a small space

What evidence would suggest that the fluid in the nucleus is different from the cytoplasm?

C) Nuclear pores only permit passage of certain molecules into and out of the nucleus.

Kidney dialysis relies on diffusion of various dissolved waste molecules (solutes) across a non-living semipermeable membrane. If the concentration of solutes in the blood increases over time before dialysis is administered, what will happen to the rate of dialysis when it occurs?

C) The rate will speed up since the concentration gradient is higher.

Radioactive isotopes are used to tag proteins in the cell membranes of mouse cells. These cells are then fused with human cells in cultures. What is the likely outcome of the tagged mouse proteins?

C) The tagged proteins drift across cell membranes and are soon found dispersed across both human and mouse cell membranes.

Which of the following statements is true regarding the inside and outside of the plasma membrane?

C) There are phospholipids on both sides of the membrane, but cytoskeletal filaments are present on the inside and carbohydrates and glycolipids are present on the outside.

Of the following conditions, which is absolutely necessary for diffusion to take place?

C) a concentration difference

The number of mitochondria in a cell would be a general indicator of the extent of

C) active transport

The cell theory states

C) all organisms are composed of cells.

You are looking at a cell under the microscope, and see what appears to be several "X" structures being pulled to each side of the cell. What stage of meiosis are you looking at?

C) anaphase I

Thylakoids and cristae are, respectively, structures of

C) chloroplasts and mitochondria.

Which nuclear structure(s) contain(s) the hereditary material?

C) chromatin

Once a solute and a solvent are evenly distributed in a solution, they will

C) continue to move about but with no net gain in any direction

You are looking at a single chromosome in a human being. Assuming there is no crossing over, what is the source of all the genes on this chromosome?

C) either the mother or father

Hormones that deliver a signal to the plasma membrane of target cells are known as

C) growth factors

Which of the following would be a function of the peroxisomes?

C) help germinating seeds convert fatty acids into molecules that can be converted to sugars

During which stage of the cell cycle do the chromosomes duplicate?

C) interphase

Active transport

C) is associated with large numbers of mitochondria.

An isotonic solution means that the solute concentration outside the cell

C) is the same as inside the cell

In which stage of mitosis do the chromosomes line up in the center of the cell?

C) metaphase

Which of these is mismatched?

C) mitochondria-stroma

Cellular respiration is most closely associated with the

C) mitochondrion

Following a cut or scrape, which process repairs your skin?

C) mitosis

Which of the following correctly describes apoptosis?

C) nucleus fragments

Blood type is determined by proteins. Blood type A has a different protein than blood type B. Blood type AB has both types of proteins and type O does not have either type of protein. When blood is transfused, the recipient's immune system will detect any new or foreign proteins. The blood type proteins must be located

C) on the outer surface of the red blood cell membrane.

In plants, chloroplasts are necessary for

C) photosynthesis

Which type of genes, when abnormally activated, can result in cancer?

C) proto-oncogenes

Which of the following cell organelles is a good target for antibacterial drugs?

C) ribosomes

Without considering the variation provided by crossing-over, how much will two siblings from one set of parents vary from each other?

C) siblings inherit essentially 50% of their genes from each parent, but two sibling offspring may share with each other from 0 to 23 chromosomes in common from each parent and therefore vary widely from each other

The formation of sperm is termed

C) spermatogenesis

When a plant cell is placed in a hypotonic solution, the cell wall prevents

C) the cell from bursting.

If a cell stops at the G1 checkpoint, this is most likely due to what problem?

C) there is DNA damage

Proteins do NOT pass through cell membranes because

C) they are very large molecules

In the emergency room, saline solutions are often run into a person's vein. The saline solution must be

D) 0.9% NaCl.

An organism has 8 pairs of chromosomes in each somatic cell. If the sperm and egg did not undergo meiosis, how many chromosomes would be present in a cell that resulted from the fusion of a sperm and egg?

D) 32

If their sperm contain 32 chromosomes, how many chromosomes do diploid cells in horses contain?

D) 64

Which of the following best characterizes apoptosis?

D) Apoptosis plays a normal role in development and cancer prevention.

Which of the following is the correct sequence for the cell cycle?

D) G1-S-G2-M

Upon examination, a cell is found to have twice as much DNA as the normal diploid state but is no longer in the process of replicating the DNA. All of the DNA is found within a single nucleus. Which phase of the cell cycle is this cell in?

D) G2

Two solutions are separated by a selectively permeable membrane. On side A, there is a solution composed of 20% protein and 80% water. On side B, the solution is 100% water. As osmosis occurs, what will happen to the solution on side A?

D) It will become less concentrated since water passes from B to A.

Ribosomes are composed of

D) RNA and protein.

How does cell division differ between animal and plant cells?

D) The cell plate is the final partitioning of plant cells.

What property of phospholipids make them suitable for the formation of the double layer found in membranes?

D) They have both a hydrophobic and a hydrophilic end.

What will happen to dye crystals if placed in the bottom of a beaker of water?

D) They will diffuse equally throughout the beaker.

You are examining a cell under the microscope that is undergoing cell division and cannot find any asters. What else would be absent in this cell?

D) a cleavage furrow

The term hypertonic means

D) a lower solute concentration

Which organelle will take in carbon dioxide and give off oxygen and water?

D) chloroplast

Molecules such as glucose and amino acids are not lipid soluble and therefore they

D) combine with carrier proteins and pass across the cell membrane by facilitated transport.

A student sitting in the back row opened a bottle of foul-smelling perfume and dabbed it on her wrists. One by one (beginning from the back of the room), the students began to cough due to the foul smell. This phenomenon was due to

D) diffusion (particles)

Mitochondria are bounded by a double membrane. The inner-filled space is called the matrix, which contains____that break down carbohydrate products, releasing ____to be used for ATP production.

D) enzymes/energy

Which components of a cell membrane are used for cell-to-cell recognition?

D) glycoproteins

If you have a 10% sugar solution and a 35% sugar solution, the 10% solution is ______

D) hypotonic

The plasma membrane is composed primarily of

D) lipids and proteins

When viewed through a microscope, one characteristic of living cells is that their internal structures move. What organelles are most directly responsible for this motion we see?

D) mitochondria and cytoskeleton

The motor molecules associated with actin filaments in muscle cells are called

D) myosin

Both plant and animal cells have mitochondria because they both

D) need ATP for energy.

Within eukaryotic cells, which organelle is surrounded by a double membrane and carries the coding that determines protein synthesis?

D) nucleus

Oogenesis

D) occurs in the ovary and produces eggs with 23 chromosomes

A basic difference between spermatogenesis and oogenesis is that in oogenesis

D) one functional egg is produced

A researcher samples the waters of the boiling hot springs in Yellowstone National Park. Under the microscope, she observes what appear to be living cells in the water. If these indeed are living cells, which type of cell would they most likely be?

D) prokaryotic, archaea

Synapsis occurs during what stage of meiosis?

D) prophase I

Which sequence of stages in mitosis is correct?

D) prophase, prometaphase, metaphase, anaphase, telophase

Which type of membrane protein will bind to hormones?

D) receptor proteins

Proteins are processed and modified in the interior of the

D) rough endoplasmic reticulum.

Which of the following processes occurs in both mitosis and meiosis?

D) single chromosomes line up along the metaphase plate

Which of the following is a correct association?

D) sister chromatids-two identical chromosome strands still attached at the centromere

During photosynthesis, solar energy is converted to chemical energy by the chloroplasts. The process is represented by

D) solar energy+carbon dioxide+water-carbohydrate+oxygen.

Consider these two examples of tissues:

D) the general concept of life-is-cellular still holds, since these organisms still utilize cells at some time in their life cycles, though these examples show that cell membranes can be abandoned.

Dead plants seen alongside a salted roadway died because the saline solution caused the cells to

D) undergo plasmolysis

Where are pigments and toxins stored in plant cells?

D) vacuole

The extracellular matrix is responsible for which of the following features?

E) All of the answer choices are correct.

Why are two children born to the same parents (not identical twins) unlikely to have the same genetic makeup?

E) All of the answer choices lead to genetic differences among siblings

The endosymbiotic theory argues that prokaryotic cells became some of the organelles of early eukaryotic cells. Which of the following supports this theory?

E) All the answers support the endosymbiotic theory.

Which of the following is a correct association?

E) G2 stage-the cell synthesizes the proteins needed for cell division

Tissues that produce large amounts of secretions, such as the gastric glands of the stomach, contain cells with large numbers of

E) Golgi apparatus.

Which statement is true concerning movement of molecules across the cell membrane?

E) Lipid molecules pass through easily.

Our body recognizes the foreign nature of a parasite or disease agent and we soon build up antibodies. A few parasites can change their identity to evade our immune system. How could cells do this on a regular basis?

E) New glycoproteins, similar to those found on the host cells, are produced in the cell and moved into the plasma membrane.

When a substance moves from an area of low concentration to an area of high concentration while using energy, the process is termed

E) active transport

Growth factors that are transported through the blood play what role in the cell cycle?

E) an external signal to tell the cell whether or not to divide

Surface-area-to-volume ratios indicate

E) as cells get larger, their surface area gets larger but at a slower rate than the volume increases.

Which of the following is a prokaryotic cell?

E) bacterium

Carrier molecules are required for

E) both facilitated diffusion AND active transport

Which of these is unique to plant cells?

E) chloroplasts

Which organelle will give off oxygen and use up carbon dioxide in plants?

E) chloroplasts

During crossing-over,

E) chromatids exchange segments of genetic material.

In a certain group of people, males are more subject to respiratory infections and are sterile. The most likely explanation for this disease is malfunctioning

E) cilia and flagella.

Which membrane transport process can continue whether the cell is alive or dead?

E) diffusion

Which is a correct association of protein types?

E) enzymatic proteins-carry out metabolic reactions directly

During interphase

E) hereditary material duplicates itself.

When a lysosome fuses with a vacuole,

E) its contents are digested.

According to the cell theory

E) new cells arise only from preexisting cells.

Which organelle primarily functions to package or regulate the production of H2O?

E) peroxisome

Macrophages, a type of white blood cells, are able to remove bacteria from our bloodstream and tissues by

E) phagocytosis

According to the fluid-mosaic model of membrane structure

E) proteins float inside or within the phospholipid bilayer.

When you add sugar to your coffee or tea, the sugar is the

E) solute

The nuclear membrane reappears in mitosis during

E) telophase

In the new procedures developed to clone a mammalian cell, the nucleus is removed from an egg cell and the nucleus from the adult to be cloned is injected inside this cell. If we did this process with a basketball, we would permanently damage the shell. What property of the cell repairs this damage?

E) the fluid-mosaic nature of the membrane

Which of the following is a correct association of cell organelles and function?

E) vacuole-storage of chemicals

According to the endosymbiotic theory, early eukaryotic cells became the mitochondria and chloroplasts found in prokaryotic cells.

FALSE

Actin filaments, intermediate filaments, and microtubules are all similar in that each is composed of a single type of protein

FALSE

All cells must have centrioles in order to divide via mitosis or meiosis

FALSE

Because mitochondria were once independently living prokaryotic cells, if removed from a eukaryotic cell they can survive independently. True or False?

FALSE

Centrioles are necessary to the process of mitosis in all organisms.

FALSE

Crossing-over is the only factor that is responsible for the variation that exists between offspring of one set of parents.

FALSE

During mitosis, separation of the sister chromatids ensures that each daughter cell will receive two copies of each type of chromosome.

FALSE

Exocytosis is carried out by proteins in the cell membrane

FALSE

Homologous chromosomes are genetically identical to each other

FALSE

Oxygen leaves the alveoli in the lungs and enters the capillaries by endocytosis.

FALSE

Replication of the DNA for meiosis occurs between telophase I and prophase II

FALSE

Since all organisms carry on cellular respiration, all living cells must contain mitochondria. True or False?

FALSE

The only function of apoptosis is to destroy healthy cells when they become damaged or infected.

FALSE

The overall cell cycle is dramatically different for animals than for plant cells.

FALSE

The primary plant cell wall and the bacteria cell wall are both composed of peptidoglycan.

FALSE

The same signaling molecule that binds to the receptor on the outside of the cell is used to alter gene expression in the nucleus. True or False?

FALSE

Chromosomes are attached to the spindle fibers in order to move to and from the metaphase plate.

TRUE

If a molecule crosses a plasma membrane faster than it diffuses in water, then the process is likely to involve active transport.

TRUE

If a particular molecule is brought into the cell by receptor-medicated endocytosis, then changing the receptors will change the molecule that is being transported.

TRUE

It is the secondary oocyte and not the egg that the sperm fertilizes to form a diploid organism.

TRUE

Microtubules found in spindle fibers are capable of assembling and disassembling

TRUE

Mitotic division is the normal process of cell reproduction to build and maintain the body of an organism, while meiosis takes place only in the formation of gametes for reproduction.

TRUE

One way to determine whether something is being actively transported across a membrane is to compare its rate of transport with and without a chemical that blocks ATP production.

TRUE

Since cyanobacteria do not contain chloroplasts and yet they photosynthesize, chloroplasts are not required for photosynthesis. True or False?

TRUE

Technically, mitosis refers to nuclear division and NOT cytoplasmic division.

TRUE

The chromatids are held together at a region called the centromere

TRUE

The length of DNA in each chromosome is longer than the diameter of the cell nucleus

TRUE

The only haploid stage in the animal life cycle is the gamete.

TRUE

Circulating red blood cells in your body do not contain a nucleus and other organelles. Are these cells living?

Yes, because they are actively metabolizing and once contained organelles.

During which phases of mitosis do the chromosomes look like Xs?

prophase, metaphase