Question 1

The cell cycle is regulated at the molecular level by a set of proteins known as

Accepted Answer

A)  ATPases. 
B)  separase proteins. 
C)  cohesins. 
D)  cyclins. 
A)  ATPases. 
B)  separase proteins. 
C)  cohesins. 
D)  cyclins.

Question 2

What is a cleavage furrow?

Accepted Answer

A)  a ring of vesicles forming a cell plate 
B)  an indentation between daughter prokaryotic cells 
C)  a groove in the plasma membrane between daughter nuclei 
D)  the metaphase plate where chromosomes attach to the spindle 
A)  a ring of vesicles forming a cell plate 
B)  an indentation between daughter prokaryotic cells 
C)  a groove in the plasma membrane between daughter nuclei 
D)  the metaphase plate where chromosomes attach to the spindle

Question 3

Which of the following are primarily responsible for cytokinesis in plant cells but not in animal cells?

Accepted Answer

A)  spot desmosomes 
B)  tubulin and dynein 
C)  actin and myosin 
D)  centrioles and centromeres 
E)  Golgi-derived vesicles 
A)  spot desmosomes 
B)  tubulin and dynein 
C)  actin and myosin 
D)  centrioles and centromeres 
E)  Golgi-derived vesicles

Question 4

Please use the following information to answer the question(s) below.
Nucleotides can be radiolabeled before they are incorporated into newly forming DNA and can therefore be assayed to track their incorporation. In a set of experiments, a student-faculty research team introduced labeled T nucleotides into the culture of dividing human cells at specific times.
-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

Accepted Answer

A)  the presence of the pathogen made the experiment too contaminated to trust the results. 
B)  their tissue culture methods needed to be relearned. 
C)  infection causes lymphocytes to divide more rapidly. 
D)  infection causes cell cultures in general to reproduce more rapidly. 
E)  infection causes lymphocyte cultures to skip some parts of the cell cycle. 
A)  the presence of the pathogen made the experiment too contaminated to trust the results. 
B)  their tissue culture methods needed to be relearned. 
C)  infection causes lymphocytes to divide more rapidly. 
D)  infection causes cell cultures in general to reproduce more rapidly. 
E)  infection causes lymphocyte cultures to skip some parts of the cell cycle.

Question 5

Density-dependent inhibition is explained by which of the following?

Accepted Answer

A)  As cells become more numerous, they begin to squeeze against each other, restricting their size and ability to produce growth factors. 
B)  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. 
C)  As cells become more numerous, the cell surface proteins of adjacent cells bind to each other and send signals that inhibit cell division. 
D)  As cells become more numerous, the level of waste products increases, eventually slowing down metabolism. 
A)  As cells become more numerous, they begin to squeeze against each other, restricting their size and ability to produce growth factors. 
B)  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. 
C)  As cells become more numerous, the cell surface proteins of adjacent cells bind to each other and send signals that inhibit cell division. 
D)  As cells become more numerous, the level of waste products increases, eventually slowing down metabolism.

Question 6

Diatoms and some yeasts are unicellular eukaryotes that have mechanisms of nuclear division that may resemble intermediate steps in the evolution of mitosis. Which of the following is a characteristic feature of nuclear division in these organisms?

Accepted Answer

A)  They have circular chromosomes that are segregated by attachment to the plasma membrane. 
B)  They have circular chromosomes that are segregated by attachment to spindle microtubules. 
C)  Chromosomes are not condensed during nuclear division. 
D)  The nuclear envelope remains intact during division. 
A)  They have circular chromosomes that are segregated by attachment to the plasma membrane. 
B)  They have circular chromosomes that are segregated by attachment to spindle microtubules. 
C)  Chromosomes are not condensed during nuclear division. 
D)  The nuclear envelope remains intact during division.

Question 7

Where are the motor proteins that move chromosomes toward the poles of the mitotic spindle located?

Accepted Answer

A)  on the centrioles 
B)  in the centrosomes 
C)  on the kinetochores 
D)  along the length of kinetochore microtubules 
A)  on the centrioles 
B)  in the centrosomes 
C)  on the kinetochores 
D)  along the length of kinetochore microtubules

Question 8

A cell in G2 of the cell division cycle contains 20 chromatids. How many centromeres are present in this cell?

Accepted Answer

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

Question 9

Besides the ability of some cancer cells to divide uncontrollably, what else could logically result in a tumor?

Accepted Answer

A)  enhanced anchorage dependence 
B)  changes in the order of cell cycle stages 
C)  lack of appropriate cell death 
D)  inability to form spindles 
A)  enhanced anchorage dependence 
B)  changes in the order of cell cycle stages 
C)  lack of appropriate cell death 
D)  inability to form spindles

Question 10

The beginning of anaphase is indicated by which of the following?

Accepted Answer

A)  loss of kinetochores from sister chromatids 
B)  enzymatic cleavage of cohesin 
C)  joining of the sister chromatids to each other by cohesin 
D)  polymerization of spindle microtubules 
A)  loss of kinetochores from sister chromatids 
B)  enzymatic cleavage of cohesin 
C)  joining of the sister chromatids to each other by cohesin 
D)  polymerization of spindle microtubules

Question 11

Which of the following is true concerning cancer cells?

Accepted Answer

A)  They exhibit density-dependent inhibition when growing in culture. 
B)  They must be attached to a substrate to divide in culture. 
C)  They evade the normal controls that trigger programmed cell death. 
D)  They stop dividing in culture when growth factors are depleted. 
A)  They exhibit density-dependent inhibition when growing in culture. 
B)  They must be attached to a substrate to divide in culture. 
C)  They evade the normal controls that trigger programmed cell death. 
D)  They stop dividing in culture when growth factors are depleted.

Question 12

Please use the following information to answer the question(s) below.
The unlettered circle at the top of Figure 9.1 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.   Figure 9.1
-Which image displays the chromosomal composition of one daughter nucleus at telophase of mitosis?

Accepted Answer

A)  A 
B)  B 
C)  C 
D)  D 
E)  E 
A)  A 
B)  B 
C)  C 
D)  D 
E)  E

Question 13

Figure 9.3
-In Figure 9.3, which of the numbered regions would contain cells at metaphase?

Accepted Answer

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

Question 14

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?

Accepted Answer

A)  8; 8 
B)  8; 16 
C)  16; 8 
D)  16; 16 
E)  12; 16 
A)  8; 8 
B)  8; 16 
C)  16; 8 
D)  16; 16 
E)  12; 16

Question 15

Figure 9.3
-In Figure 9.3, which number represents the point in the cell cycle during which the chromosomes are replicated?

Accepted Answer

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

Question 16

Figure 9.3
-In Figure 9.3, G1 is represented by which numbered parts of the cycle?

Accepted Answer

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

Question 17

Researchers began a study of a cultured cell line. Their preliminary observations showed them that the cell line did not exhibit either density-dependent inhibition or anchorage dependence. What could they conclude right away?

Accepted Answer

A)  The cells originated in the nervous system. 
B)  The cells show characteristics of tumors. 
C)  The cells have altered series of cell cycle phases. 
D)  The cells were originally derived from an elderly organism. 
A)  The cells originated in the nervous system. 
B)  The cells show characteristics of tumors. 
C)  The cells have altered series of cell cycle phases. 
D)  The cells were originally derived from an elderly organism.

Question 18

Most animal cells exhibit anchorage dependence, which means that in order to divide

Accepted Answer

A)  all chromosomes must be attached to spindle microtubules. 
B)  nonkinetochore microtubules from opposite poles must overlap and be attached by motor proteins. 
C)  cell-surface phospholipids must be attached to those of adjoining cells. 
D)  cells must be attached to a substrate or extracellular matrix of a tissue. 
A)  all chromosomes must be attached to spindle microtubules. 
B)  nonkinetochore microtubules from opposite poles must overlap and be attached by motor proteins. 
C)  cell-surface phospholipids must be attached to those of adjoining cells. 
D)  cells must be attached to a substrate or extracellular matrix of a tissue.

Question 19

Figure 9.3
-In Figure 9.3, DNA synthesis is represented by which numbered parts of the cycle?

Accepted Answer

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

Question 20

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?

Accepted Answer

A)  Cancer cells replicate chromosomes multiple times per cell cycle. 
B)  Cancer cells are no longer anchorage dependent. 
C)  Cell cycle checkpoints are not in place to stop cells with chromosome abnormalities. 
D)  Cells with abnormal chromosomes have increased metabolism. 
A)  Cancer cells replicate chromosomes multiple times per cell cycle. 
B)  Cancer cells are no longer anchorage dependent. 
C)  Cell cycle checkpoints are not in place to stop cells with chromosome abnormalities. 
D)  Cells with abnormal chromosomes have increased metabolism.

Exam 9: The Cell Cycle

The cell cycle is regulated at the molecular level by a set of proteins known as

What is a cleavage furrow?

Which of the following are primarily responsible for cytokinesis in plant cells but not in animal cells?

Density-dependent inhibition is explained by which of the following?

Diatoms and some yeasts are unicellular eukaryotes that have mechanisms of nuclear division that may resemble intermediate steps in the evolution of mitosis. Which of the following is a characteristic feature of nuclear division in these organisms?

Where are the motor proteins that move chromosomes toward the poles of the mitotic spindle located?

A cell in G2 of the cell division cycle contains 20 chromatids. How many centromeres are present in this cell?

Besides the ability of some cancer cells to divide uncontrollably, what else could logically result in a tumor?

The beginning of anaphase is indicated by which of the following?

Which of the following is true concerning cancer cells?

Figure 9.3 -In Figure 9.3, which of the numbered regions would contain cells at metaphase?

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?

Figure 9.3 -In Figure 9.3, which number represents the point in the cell cycle during which the chromosomes are replicated?

Figure 9.3 -In Figure 9.3, G1 is represented by which numbered parts of the cycle?

Researchers began a study of a cultured cell line. Their preliminary observations showed them that the cell line did not exhibit either density-dependent inhibition or anchorage dependence. What could they conclude right away?

Most animal cells exhibit anchorage dependence, which means that in order to divide

Figure 9.3 -In Figure 9.3, DNA synthesis is represented by which numbered parts of the cycle?

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?

Introduction: Evolution and the Foundations of Biology

The Chemical Context of Life

Carbon and the Molecular Diversity of Life

A Tour of the Cell

Membrane Transport and Cell Signaling

An Introduction to Metabolism

Cellular Respiration and Fermentation

Photosynthesis

Meiosis and Sexual Life Cycles

Mendel and the Gene Idea

The Chromosomal Basis of Inheritance

The Molecular Basis of Inheritance

Gene Expression: From Gene to Protein

Regulation of Gene Expression

Development, Stem Cells, and Cancer

Viruses

Genomes and Their Evolution

Descent With Modification

Phylogeny

The Evolution of Populations

The Origin of Species

Broad Patterns of Evolution

Early Life and the Diversification of Prokaryotes

The Origin and Diversification of Eukaryotes

The Colonization of Land by Plants and Fungi

The Rise of Animal Diversity

Plant Structure and Growth

Resource Acquisition, Nutrition, and Transport in Vascular Plants

Reproduction and Domestication of Flowering Plants

Plant Responses to Internal and External Signals

Homeostasis and Endocrine Signaling

Animal Nutrition

Circulation and Gas Exchange

The Immune System

Reproduction and Development

Neurons, Synapses, and Signaling

Nervous and Sensory Systems

Motor Mechanisms and Behavior

Population Ecology and the Distribution of Organisms

Species Interactions

Ecosystems and Energy

Global Ecology and Conservation Biology

Filters