Question 1

Cells from an advanced malignant tumor most often have very abnormal chromosomes, and often an abnormal total number of chromosomes. Why might this occur?

Accepted Answer

A) Cancer cells are no longer density dependent. 
B) Cancer cells are no longer anchorage dependent. 
C) Chromosomally abnormal cells can still go through cell cycle checkpoints. 
D) Chromosomally abnormal cells still have normal metabolism. 
E) Transformation introduces new chromosomes into cells. 
A) Cancer cells are no longer density dependent. 
B) Cancer cells are no longer anchorage dependent. 
C) Chromosomally abnormal cells can still go through cell cycle checkpoints. 
D) Chromosomally abnormal cells still have normal metabolism. 
E) Transformation introduces new chromosomes into cells.

Question 2

One difference between cancer cells and normal cells is that cancer cells

Accepted Answer

A) are unable to synthesize DNA. 
B) are arrested at the S phase of the cell cycle. 
C) continue to divide even when they are tightly packed together. 
D) cannot function properly because they are affected by density-dependent inhibition. 
E) are always in the M phase of the cell cycle. 
A) are unable to synthesize DNA. 
B) are arrested at the S phase of the cell cycle. 
C) continue to divide even when they are tightly packed together. 
D) cannot function properly because they are affected by density-dependent inhibition. 
E) are always in the M phase of the cell cycle.

Question 3

The following questions are based on Figure 12.3.
  
-Which number represents DNA synthesis?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
E) V 
A) I 
B) II 
C) III 
D) IV 
E) V

Question 4

Nerve and muscle cells are in this phase:

Accepted Answer

A) G₀ 
B) G₁ 
C) S 
D) G₂ 
E) M 
A) G₀ 
B) G₁ 
C) S 
D) G₂ 
E) M

Question 5

The best conclusion concerning delta is that the cells

Accepted Answer

A) contain no DNA. 
B) contain no RNA. 
C) contain only one chromosome that is very short. 
D) are actually in the G₀ phase. 
E) divide in the G₁ phase. 
A) contain no DNA. 
B) contain no RNA. 
C) contain only one chromosome that is very short. 
D) are actually in the G₀ phase. 
E) divide in the G₁ phase.

Question 6

Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants

Accepted Answer

A) the spindles contain microfibrils in addition to microtubules, whereas animal spindles do not contain microfibrils. 
B) sister chromatids are identical, but they differ from one another in animals. 
C) a cell plate begins to form at telophase, whereas in animals a cleavage furrow is initiated at that stage. 
D) chromosomes become attached to the spindle at prophase, whereas in animals chromosomes do not become attached until anaphase. 
E) spindle poles contain centrioles, whereas spindle poles in animals do not. 
A) the spindles contain microfibrils in addition to microtubules, whereas animal spindles do not contain microfibrils. 
B) sister chromatids are identical, but they differ from one another in animals. 
C) a cell plate begins to form at telophase, whereas in animals a cleavage furrow is initiated at that stage. 
D) chromosomes become attached to the spindle at prophase, whereas in animals chromosomes do not become attached until anaphase. 
E) spindle poles contain centrioles, whereas spindle poles in animals do not.

Question 7

These Protists are intermediate in what sense?

Accepted Answer

A) They reproduce by binary fission in their early stages of development and by mitosis when they are mature. 
B) They never coil up their chromosomes when they are dividing. 
C) They use mitotic division but only have circular chromosomes. 
D) They maintain a nuclear envelope during division. 
E) None of them form spindles. 
A) They reproduce by binary fission in their early stages of development and by mitosis when they are mature. 
B) They never coil up their chromosomes when they are dividing. 
C) They use mitotic division but only have circular chromosomes. 
D) They maintain a nuclear envelope during division. 
E) None of them form spindles.

Question 8

Use the following information to answer the questions below.
The lettered circle in Figure 12.1 shows a diploid nucleus with four chromosomes. There are two pairs of homologous chromosomes, one long and the other short. One haploid set is symbolized as black and the other haploid set is gray. The chromosomes in the unlettered circle have not yet replicated. Choose the correct chromosomal conditions for the following stages.

-Which is the longest of the mitotic stages?

Accepted Answer

A) telophase 
B) anaphase 
C) prometaphase 
D) metaphase 
E) prophase 
A) telophase 
B) anaphase 
C) prometaphase 
D) metaphase 
E) prophase

Question 9

If there are 20 chromatids in a cell, how many centromeres are there?

Accepted Answer

A) 10 
B) 20 
C) 30 
D) 40 
E) 80 
A) 10 
B) 20 
C) 30 
D) 40 
E) 80

Question 10

Use the following information to answer the questions below.
The lettered circle in Figure 12.1 shows a diploid nucleus with four chromosomes. There are two pairs of homologous chromosomes, one long and the other short. One haploid set is symbolized as black and the other haploid set is gray. The chromosomes in the unlettered circle have not yet replicated. Choose the correct chromosomal conditions for the following stages.

-Which term describes centrioles beginning to move apart in animal cells?

Accepted Answer

A) telophase 
B) anaphase 
C) prometaphase 
D) metaphase 
E) prophase 
A) telophase 
B) anaphase 
C) prometaphase 
D) metaphase 
E) prophase

Question 11

The MPF protein complex turns itself off by

Accepted Answer

A) activating a process that destroys cyclin component. 
B) activating an enzyme that stimulates cyclin. 
C) binding to chromatin. 
D) exiting the cell. 
E) activating the anaphase-promoting complex. 
A) activating a process that destroys cyclin component. 
B) activating an enzyme that stimulates cyclin. 
C) binding to chromatin. 
D) exiting the cell. 
E) activating the anaphase-promoting complex.

Question 12

In which group of eukaryotic organisms does the nuclear envelope remain intact during mitosis?

Accepted Answer

A) seedless plants 
B) dinoflagellates 
C) diatoms 
D) B and C only 
E) A, B, and C 
A) seedless plants 
B) dinoflagellates 
C) diatoms 
D) B and C only 
E) A, B, and C

Question 13

The research team established similar lymphocyte cultures from a number of human donors, including healthy teenagers of both genders, patients already suffering from long-term bacterial infections, and elderly volunteers. They found that the increase in lymphocyte incorporation after pathogen introduction was slightly lower in some of the women teenagers and significantly lower in each of the elderly persons. They repeated the study with a larger number of samples but got the same results. What might be among their conclusions?

Accepted Answer

A) The young women showed these results because they have poorer nutrition. 
B) The elderly persons' samples demonstrated their lowered immune responses. 
C) The young men had higher response because they are generally healthier. 
D) The patient samples should have had the lowest response but did not, so the experiment is invalid. 
E) The elderly donor samples represent cells no longer capable of any cell division. 
A) The young women showed these results because they have poorer nutrition. 
B) The elderly persons' samples demonstrated their lowered immune responses. 
C) The young men had higher response because they are generally healthier. 
D) The patient samples should have had the lowest response but did not, so the experiment is invalid. 
E) The elderly donor samples represent cells no longer capable of any cell division.

Question 14

Cytokinesis usually, but not always, follows mitosis. If a cell completed mitosis but not cytokinesis, the result would be a cell with

Accepted Answer

A) a single large nucleus. 
B) high concentrations of actin and myosin. 
C) two abnormally small nuclei. 
D) two nuclei. 
E) two nuclei but with half the amount of DNA. 
A) a single large nucleus. 
B) high concentrations of actin and myosin. 
C) two abnormally small nuclei. 
D) two nuclei. 
E) two nuclei but with half the amount of DNA.

Question 15

Proteins that are involved in the regulation of the cell cycle, and that show fluctuations in concentration during the cell cycle, are called

Accepted Answer

A) ATPases. 
B) kinetochores. 
C) centrioles. 
D) proton pumps. 
E) cyclins. 
A) ATPases. 
B) kinetochores. 
C) centrioles. 
D) proton pumps. 
E) cyclins.

Question 16

Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, taxol disrupts microtubule formation by binding to microtubules and accelerating their assembly from the protein precursor, tubulin. Surprisingly, this stops mitosis. Specifically, taxol must affect

Accepted Answer

A) the fibers of the mitotic spindle. 
B) anaphase. 
C) formation of the centrioles. 
D) chromatid assembly. 
E) the S phase of the cell cycle. 
A) the fibers of the mitotic spindle. 
B) anaphase. 
C) formation of the centrioles. 
D) chromatid assembly. 
E) the S phase of the cell cycle.

Question 17

Which of the following are primarily responsible for cytokinesis in plant cells?

Accepted Answer

A) kinetochores 
B) Golgi-derived vesicles 
C) actin and myosin 
D) centrioles and basal bodies 
E) cyclin-dependent kinases 
A) kinetochores 
B) Golgi-derived vesicles 
C) actin and myosin 
D) centrioles and basal bodies 
E) cyclin-dependent kinases

Question 18

This is the shortest part of the cell cycle:

Accepted Answer

A) G₀ 
B) G₁ 
C) S 
D) G₂ 
E) M 
A) G₀ 
B) G₁ 
C) S 
D) G₂ 
E) M

Question 19

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in

Accepted Answer

A) cells with more than one nucleus. 
B) cells that are unusually small. 
C) cells lacking nuclei. 
D) destruction of chromosomes. 
E) cell cycles lacking an S phase. 
A) cells with more than one nucleus. 
B) cells that are unusually small. 
C) cells lacking nuclei. 
D) destruction of chromosomes. 
E) cell cycles lacking an S phase.

Question 20

The somatic cells derived from a single-celled zygote divide by which process?

Accepted Answer

A) meiosis 
B) mitosis 
C) replication 
D) cytokinesis alone 
E) binary fission 
A) meiosis 
B) mitosis 
C) replication 
D) cytokinesis alone 
E) binary fission

Exam 12: The Cell Cycle

Cells from an advanced malignant tumor most often have very abnormal chromosomes, and often an abnormal total number of chromosomes. Why might this occur?

One difference between cancer cells and normal cells is that cancer cells

The following questions are based on Figure 12.3. -Which number represents DNA synthesis?

Nerve and muscle cells are in this phase:

The best conclusion concerning delta is that the cells

Regarding mitosis and cytokinesis, one difference between higher plants and animals is that in plants

These Protists are intermediate in what sense?

If there are 20 chromatids in a cell, how many centromeres are there?

The MPF protein complex turns itself off by

In which group of eukaryotic organisms does the nuclear envelope remain intact during mitosis?

Cytokinesis usually, but not always, follows mitosis. If a cell completed mitosis but not cytokinesis, the result would be a cell with

Proteins that are involved in the regulation of the cell cycle, and that show fluctuations in concentration during the cell cycle, are called

Taxol is an anticancer drug extracted from the Pacific yew tree. In animal cells, taxol disrupts microtubule formation by binding to microtubules and accelerating their assembly from the protein precursor, tubulin. Surprisingly, this stops mitosis. Specifically, taxol must affect

Which of the following are primarily responsible for cytokinesis in plant cells?

This is the shortest part of the cell cycle:

In the cells of some organisms, mitosis occurs without cytokinesis. This will result in

The somatic cells derived from a single-celled zygote divide by which process?

Introduction: Themes in the Study of Life

The Chemical Context of Life

Water and the Fitness of the Environment

Carbon and the Molecular Diversity of Life

The Structure and Function of Large Biological Molecules

A Tour of the Cell

Membrane Structure and Function

An Introduction to Metabolism

Cellular Respiration: Harvesting Chemical Energy

Photosynthesis

Cell Communication

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

From Gene to Protein

Control of Gene Expression

Viruses

Biotechnology

Genomes and Their Evolution

Descent With Modification: a Darwinian View of Life

The Evolution of Populations

The Origin of Species

The History of Life on Earth

Phylogeny and the Tree of Life

Bacteria and Archaea

Protists

Plant Diversity I: How Plants Colonized Land

Plant Diversity Ii: the Evolution of Seed Plants

Fungi

An Introduction to Animal Diversity

Invertebrates

Vertebrates

Plant Structure, Growth, and Development

Transport in Vascular Plants

Soil and Plant Nutrition

Angiosperm Reproduction and Biotechnology

Plant Responses to Internal and External Signals

Basic Principles of Animal Form and Function

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Osmoregulation and Excretion

Hormones and the Endocrine System

Animal Reproduction

Animal Development

Neurons, Synapses, and Signaling

Nervous Systems

Sensory and Motor Mechanisms

Animal Behavior

An Introduction to Ecology and the Biosphere

Population Ecology

Community Ecology

Ecosystems

Conservation Biology and Restoration Ecology

Filters