AP Bio Cell Division and Communication Test Review

Assume that you are dealing with a species in which the number of chromosomes in each somatic cell is 14. How many sister chromatids are present in the early telophase of mitosis?

0

If there are 20 centromeres in a cell at anaphase of mitosis, how many chromosomes are there in each daughter cell following cytokinesis? -10 -20 -40 -5

10

A cell biologist carefully measured the quantity of DNA in grasshopper cells growing in cell culture. Cells examined during the G2 phase of the cell cycle each contained 200 units of DNA. What would be the amount of DNA at G1 of the cell cycle in a daughter cell of one of these cells?

100 units

A group of cells is assayed for DNA content immediately following mitosis and is found to have an average of 8 picograms of DNA per nucleus. How many picograms would be found at the end of S and the end of G2? -8; 16 -16; 8 -8; 8 -16; 16 -12; 16

16; 16

When not engaged in the processes leading to cell division, how many chromosomes from your mother are present in the nucleus of each of your somatic cells?

23

Beginning with a fertilized egg (zygote), a series of five cell divisions would produce an early embryo with how many cells? -4 -64 -16 -32 -8

32

If a human somatic cell is in metaphase, it has __________ chromatids.

92

Down syndrome is characterized by cells having three copies of chromosome 21. As a somatic cell in an individual with Down syndrome prepares to enter mitosis, how many chromatids would be present in the cell's nucleus?

94

Which of the following cells would release interferon?

A cell infected by a virus

Major histocompatibility complex molecules __________. -are involved in the ability to distinguish self from nonself -are a collection of cell surface proteins -may trigger T cell responses after transplant operations present antigen fragments on infected cells -All of the listed responses are correct.

All of the listed responses are correct.

Monoclonal antibodies differ from polyclonal antibodies in that they are __________. -specific for a single epitope -produced outside of a living vertebrate -the basis for pregnancy tests -used more often as new therapies for disease -All of the listed responses are correct.

All of the listed responses are correct.

Which of the following is a specific mechanism by which antibodies function in immunity? -Neutralization of viruses -Linking bacteria into aggregates -Activation of complement system -Recruitment of natural killer cells to destroy virus-infected body cells -All of the listed responses are correct.

All of the listed responses are correct.

Which of the following is not a disease caused by actions of the immune system? -Crohn's disease -Ulcerative colitis -Lupus -Rheumatoid arthritis -All of the listed responses are correct.

All of the listed responses are correct.

Which of the following statements best describes an insect's immune system? -Insects rely on the barrier defense of an exoskeleton. -Lysozyme attacks bacterial cell walls, protecting an insect's digestive system. -Hemocytes carry out phagocytosis of bacteria and foreign substances. -Insects produce antimicrobial peptides in response to a broad class of pathogens. -All of the listed responses are correct.

All of the listed responses are correct.

Density-dependent inhibition is explained by which of the following? -As cells become more numerous, the protein kinases they produce begin to compete with each other, such that the proteins produced by one cell essentially cancel those produced by its neighbor. -As cells become more numerous, they begin to squeeze against each other, restricting their size and ability to produce growth factors. -As cells become more numerous, the cell surface proteins of adjacent cells bind to each other and send signals that inhibit cell division. -As cells become more numerous, the level of waste products increases, eventually slowing down metabolism.

As cells become more numerous, the cell surface proteins of adjacent cells bind to each other and send signals that inhibit cell division.

Lymphocytes are screened for self-reactivity in what part of the body?

Bone marrow and thymus

Someone infected by chicken pox once as a child is unlikely to suffer from this disease a second time. This is due to immunological memory, a reservoir of what type of cells generated following the initial exposure?

Both T cells and B cells

Cells from advanced malignant tumors frequently have very abnormal chromosomes as well as an abnormal number of chromosomes. What might explain the association between malignant tumors and chromosomal abnormalities? -Cells with abnormal chromosomes have increased metabolism. -Cancer cells are no longer anchorage dependent. -Cell cycle checkpoints are not in place to stop cells with -chromosome abnormalities. -Cancer cells replicate chromosomes multiple times per cell cycle.

Cell cycle checkpoints are not in place to stop cells with chromosome abnormalities.

What is the difference between a benign tumor and a malignant tumor?

Cells of benign tumors do not metastasize; those of malignant tumors do.

The cleavage furrow forms during which stage of mitosis and cell division of an animal cell?

Cytokinesis

Eukaryotic chromatin is composed of -DNA and RNA -DNA and carbohydrates -DNA and ribosomes -condensed DNA only -DNA and proteins

DNA and proteins

Which of the following does not occur during mitosis?

Duplication of chromosomes

The unlettered circle at the top of the Figure below shows a diploid nucleus with four chromosomes that have not yet replicated. There are two pairs of homologous chromosomes, one long and the other short. One haploid set is black, and the other is gray. The circles labeled A-E show various combinations of these chromosomes. Which image displays the chromosomal composition of one daughter nucleus at telophase of mitosis? -E -A -C -D -B

E

What proportion of immunized children experience side effects of the measles vaccine?

Fewer than one in a million

A particular cell has half as much DNA as some other cells in a mitotically active tissue. The cell in question is most likely in -metaphase. -G1. -G2. -prophase.

G1

Which is the first checkpoint in the cell cycle where a cell will be caused to exit the cycle if this point is not passed? -G2 -M -G1 -G0 -S

G1

Which of the following are primarily responsible for cytokinesis in plant cells but not in animal cells? -tubulin and dynein -centrioles and centromeres -actin and myosin -Golgi-derived vesicles

Golgi-derived vesicles

In the figure below, which number represents the point in the cell cycle during which the chromosomes are replicated? -II -I -V -IV -III

II

In the figure below, which of the numbered regions would contain cells at metaphase? -V only -IV only -II only -I and IV only -III only

III only

In the figure below, mitosis is represented by which numbered parts of the cycle? -III -V -I -IV -II

IV

Which of the following is not a characteristic of innate immunity?

It is present only in vertebrates.

For a chemotherapeutic drug to be useful for treating cancer cells, which of the following is most desirable? -It is safe enough to limit all apoptosis. -It does not affect metabolically active cells. -It targets only rapidly dividing cells -It only attacks cells that are density dependent.

It targets only rapidly dividing cells

Which of the following defense mechanisms is incorrectly paired with one of its functions?

Lysozyme - attacks the cell wall of viruses

Which of the following conditions is not considered a disease or malfunction of the immune system?

MHC-induced transplant rejection

Which of the following represents a mismatch or incorrect description?

Metaphase: the nuclear envelope disappears

Which of the following processes does not occur in dividing bacteria?

Mitosis

Which of the following cells does not play a role in immunity through phagocytosis of pathogens?

Natural killer cells

You would be unlikely to see which of the following human cells dividing?

Nerve cell

A cell entering mitosis with 32 chromosomes will produce daughter cells with __________. -None of the listed responses is correct. -16 chromosomes -64 chromosomes -32 pairs of chromosomes -64 pairs of chromosomes

None of the listed responses are correct. Every eukaryotic species has a characteristic number of chromosomes in each cell nucleus.

Which of the following is released by platelets in the vicinity of an injury? -separase -protein kinase -cyclin -PDGF

PDGF

You have a series of cells, all of which were derived from tumors. How might you determine which ones are malignant? -Identify the ones with higher rates of apoptosis. -Identify the ones with elongated cell cycles -Identify the ones that are not dividing uncontrollably. -Prepare karyotypes to identify the ones with aberrant chromosome number or structure

Prepare karyotypes to identify the ones with aberrant chromosome number or structure

What role do major histocompatibility complex (MHC) molecules play in immunity?

Presentation of antigens to T cells

In a human skin cell that is going through the cell cycle, when do the centrosomes separate?

Prophase

The person credited with the axiom, "Every cell from a cell" is __________.

Rudolf Virchow

A plant-derived protein known as colchicine can be used to poison cells by blocking the formation of the spindle. Which of the following would result if colchicine is added to a sample of cells in G2? -The cells would immediately die. -The chromosomes would segregate but in a disorderly pattern or not segregate at all. -The cells would be unable to begin M and stay in G2. -Chromosome condensation would fail to occur, but the chromosomes would align at the metaphase plate.

The chromosomes would segregate but in a disorderly pattern or not segregate at all.

A plant-derived protein known as colchicine can be used to poison cells by blocking the formation of the spindle. Which of the following would result if colchicine is added to a sample of cells in G2? -The chromosomes would segregate but in a disorderly pattern. -Chromosome condensation would occur, but the chromosomes would fail to align at the metaphase plate. -The cells would immediately die. -The cells would be unable to begin M and stay in G2.

The chromosomes would segregate but in a disorderly pattern.

Why are the development and distribution of a new flu vaccine required every year?

The influenza virus undergoes frequent mutations and evolves rapidly.

What accounts for the huge diversity of antigens to which B cells can respond?

The recombination within light and heavy chain genes during development results in millions of possible antigen receptors.

Why do neurons and some other specialized cells divide infrequently? -They no longer have active nuclei. -They no longer carry receptors for signal molecules. -They have been shunted into G0. -They no longer produce cyclins.

They have been shunted into G0.

Several organisms, including a number of protists, have intermediate mitotic organization. Which of the following is the most probable hypothesis regarding these intermediate forms of cell division? -They show some but not all of the evolutionary steps toward complete mitosis. -They may be more closely related to plant forms that also have unusual mitosis. -They rely on totally different proteins for the processes they undergo. -They represent a form of cell reproduction that must have evolved completely separately from those of other organisms. -They demonstrate that these species are not closely related to any of the other protists and may well be a different kingdom.

They show some but not all of the evolutionary steps toward complete mitosis.

Which of the following statements is not true of Toll-like receptors?

Toll-like receptors recognize molecules specific to individual pathogens.

Which of the following organisms would produce antibodies as part of an immune response?

Whale

When a cell is in late anaphase of mitosis, which of the following may be seen? -decondensing chromosomes clustered at the poles -nuclear envelopes forming at the poles -a clear area in the center of the dividing cell -individual chromatids beginning to separate from one another -chromosomes clustered tightly at the center of the dividing cell

a clear area in the center of the dividing cell

What is a cleavage furrow? -the metaphase plate where chromosomes attach to the spindle -an indentation between daughter prokaryotic cells -a groove in the plasma membrane between daughter nuclei -a ring of vesicles forming a cell plate

a groove in the plasma membrane between daughter nuclei

Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely -a plant cell in the process of cytokinesis. -an animal cell in the process of cytokinesis. -a plant cell in metaphase. -a bacterial cell dividing

a plant cell in the process of cytokinesis.

Through a microscope, you can see a cell plate beginning to develop across the middle of a cell and nuclei forming on either side of the cell plate. This cell is most likely -an animal cell in the process of cytokinesis. -a plant cell in the process of cytokinesis. -a bacterial cell dividing -a plant cell in metaphase.

a plant cell in the process of cytokinesis.

Immediately following binding of a growth factor, an activated receptor would most likely stimulate activation of -a calcium-binding protein -a protein kinase -adenylyl cyclase -a protein phosphatase

a protein kinase

In which of the following ways could signal transduction most probably be explored in research to treat cancer? -increase calcium ion uptake into the cytoplasm in order to modulate the effects of environmental carcinogens -alteration of protein kinases in cell cycle regulation in order to slow cancer growth -stimulation of cAMP production in cancer cells -removal of serine/threonine phosphate acceptors from transduction pathways in colon pre-cancerous growths

alteration of protein kinases in cell cycle regulation in order to slow cancer growth

The data in the Table below were obtained from a study of the length of time spent in each phase of the cell cycle by cells of three eukaryotic organisms designated beta, delta, and gamma. The best conclusion concerning delta is that the cells -contain no DNA. -are actually in the G0 phase. -contain only one chromosome that is very small. -synthesize DNA in the G1 phase

are actually in the G0 phase.

The function of mitosis and cytokinesis is to produce daughter cells that __________.

are genetically identical to the parent cell

A biochemist measured the amount of DNA in cells growing in the laboratory and found that the quantity of DNA in the cells doubled __________.

between the G1 and G2 phases.

Histamine is an important signaling molecule in the immune system that directly triggers __________.

blood vessels to dilate and become more permeable

Lysozyme plays a role in immunity through __________.

breaking down bacterial cell walls

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in -cells lacking nuclei -cells that are unusually small. -cell cycles lacking an S phase. -cells with more than one nucleus

cells with more than one nucleus

Where do the microtubules of the spindle originate during mitosis in animal cells? -centriole -kinetochore -centrosome -centromere

centrosome

The complex of DNA and protein that makes up a eukaryotic chromosome is properly called __________.

chromatin

The drug cytochalasin B blocks the function of actin, which forms a "band-like" structure around animal cells beginning in anaphase or telophase. Which of the following aspects of the animal cell cycle would be most-disrupted by cytochalasin B? -spindle attachment to kinetochores -spindle formation -cell elongation during anaphase -cleavage furrow formation and cytokinesis

cleavage furrow formation and cytokinesis

The protein complex that activates progress through the M phase checkpoint will allow which of the following to occur? -cleavage of cohesin proteins by separase -modification of separase by cohesins -assembly of spindle microtubules -disassembly of spindle microtubules at the centromere

cleavage of cohesin proteins by separase

During interphase, the genetic material of a typical eukaryotic cell is __________.

dispersed in the nucleus as long strands of chromatin

Cytokinesis refers to __________.

division of the cytoplasm

Observations of cancer cells in culture support the hypothesis that cancer cells __________.

do not exhibit density-dependent inhibition

Tissue culture experiments with PDGF demonstrate that without this substance __________.

fibroblasts fail to divide

Sister chromatids are __________.

identical copies of a chromosome

Herpes simplex viruses can evade the immune system and persist in the body by __________.

infecting cells and then entering a largely inactive state

The research team used the setup to study the incorporation of labeled nucleotides into a culture of lymphocytes and found that the lymphocytes incorporated the labeled nucleotide at a significantly higher level after a pathogen was introduced into the culture. They concluded that -their tissue culture methods needed to be relearned. -infection causes lymphocytes to divide more rapidly -infection causes cell cultures in general to reproduce more rapidly. -the presence of the pathogen made the experiment too contaminated to trust the results. -infection causes lymphocyte cultures to skip some parts of the cell cycle

infection causes lymphocytes to divide more rapidly

Anaphylactic shock is a life-threatening condition in which __________.

inflammatory chemicals released from immune cells lead to an inability to breathe and a lack of blood flow

Lipid-soluble signaling molecules, such as aldosterone, cross the membranes of all cells but affect only target cells because? -only in target cells is aldosterone able to initiate a phosphorylation cascade that turns genes on -intracellular receptors are present only in target cells -only target cell have enzymes that break down aldosterone -only target cells retain the appropriate DNA segments

intracellular receptors are present only in target cells

Passive immunity differs from active immunity in that passive immunity __________.

is conferred by antibodies produced by another individual

You would know a dividing cell was a plant cell rather than an animal cell if you saw that __________.

it had formed a cell plate

Which of the following enzymes adds a phosphate group to target proteins? -glycogen phosphorylase -adenylyl cyclase -phosphatase -kinase

kinase

Besides the ability of some cancer cells to divide uncontrollably, what else could logically result in a tumor? -inability to form spindles -lack of appropriate cell death -changes in the order of cell cycle stages -enhanced anchorage dependence

lack of appropriate cell death

A secondary immune response is more rapid and effective than a primary immune response because __________.

memory cells respond to the pathogen and rapidly proliferate into effector cells

Compared to most prokaryotic cells, eukaryotic cells typically have -fewer DNA molecules but smaller genomes -fewer DNA molecules but larger genomes -the same number of DNA molecules but larger genomes -the same number of DNA molecules but similarly sized genomes -more DNA molecules and larger genomes

more DNA molecules and larger genomes

During binary fission of a bacterium, __________.

origins of replication move apart

Which of the following correctly describes the relationship between an enzyme and its function? -phosphatase: removal of phosphate group -glycogen phosphorylase: synthesis of glycogen -adenylyl cyclase: conversion of cAMP to AMP -kinase: addition of tyrosine

phosphatase: removal of phosphate group

Clonal selection is responsible for the __________.

proliferation of effector cells and memory cells specific to an encountered antigen

During mitosis in animal cells, at which phase do centrioles begin to move apart? -metaphase -anaphase -prophase -prometaphase -telophase

prophase

The primary function of transcription factors is to -transmit signals from an activated receptor to intracellular G proteins. -regulate DNA synthesis -regulate gene expression -regulate the conversion of ATP to cAMP

regulate gene expression

Which of the following does not occur during mitosis? -condensation of the chromosomes -replication of the DNA -spindle formation -separation of sister chromatids

replication of the DNA

In general, a signal transmitted via a phosphorylation cascade -is propagated by a steroid receptor -is initiated by a phosphorylase enzyme -results in a conformational change in each phosphorylated protein -is turned off by a kinase enzyme

results in a conformational change in each phosphorylated protein

Movement of the chromosomes during anaphase would be most affected by a drug that prevents -cell wall formation -formation of cleavage furrow -nuclear envelope breakdown -shortening of microtubules -elongation of microtubules

shortening of microtubules

Which of the following types of signaling is represented in the figure below? -paracrine -hormonal -autocrine -synaptic

synaptic

One event occurring during prophase is __________.

the beginning of the formation of a mitotic spindle

Which of the following is the first event that occurs following the binding of a ligand by a membrane receptor protein? -the membrane receptor protein enters the cytoplasm. -An intracellular enzyme is activated by phosphorylation -the membrane protein undergoes a conformational change -An intracellular G protein is activated

the membrane protein undergoes a conformational change

Which of the following is true of steroid receptors? -the receptor molecules are themselves lipids or glycolipids -the receptor molecules may be soluble proteins in the cytoplasm -the receptor molecules are peripheral proteins embedded in the interior layer of the plasma membrane -the receptor molecules are transmembrane proteins with the ligand binding domain on the outside of the cell

the receptor molecules may be soluble proteins in the cytoplasm

Phosphorylation cascades involving a series of protein kinases are useful for cellular signal transduction because -they counter the harmful effects of phosphatases -they amplify the original signal manyfold -they are species specific -they always lead to the same cellular response

they amplify the original signal manyfold

Which of the following is the most likely fate of animal cells that lack receptors for local paracrine signal molecules? -they would be unable to respond to hormone signals delivered through the bloodstream -they would be grow and divide normally -They would bind locally secreted growth factors, but intracellular signal pathways would be blocked -they would be unable to grow and divide in response to growth factors from nearby cells

they would be unable to grow and divide in response to growth factors from nearby cells