Question 1

Beginning with a fertilized egg (zygote),how many cells would be present in an embryo following a series of five cell divisions?

Accepted Answer

A) 4 
B) 8 
C) 16 
D) 32 
E) 64 
A) 4 
B) 8 
C) 16 
D) 32 
E) 64

Question 2

If the cell whose nuclear material is shown in the figure above continues toward completion of mitosis,which of the following events would occur next?

Accepted Answer

A) cell membrane synthesis 
B) alignment of chromosomes at the metaphase plate 
C) segregation of daughter chromosomes toward the poles 
D) formation of telophase nuclei 
E) synthesis of sister chromatids 
A) cell membrane synthesis 
B) alignment of chromosomes at the metaphase plate 
C) segregation of daughter chromosomes toward the poles 
D) formation of telophase nuclei 
E) synthesis of sister chromatids

Question 3

-In the figure above,which numbered segment(s)of the cycle represent the period during which the chromosomes are replicated?

Accepted Answer

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

Question 4

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

Accepted Answer

A) an animal cell in the process of cytokinesis. 
B) a plant cell in the process of cytokinesis. 
C) a bacterial cell dividing. 
D) a plant cell in metaphase. 
A) an animal cell in the process of cytokinesis. 
B) a plant cell in the process of cytokinesis. 
C) a bacterial cell dividing. 
D) a plant cell in metaphase.

Question 5

Why do most cells in the human body divide infrequently?

Accepted Answer

A) They no longer have active nuclei. 
B) They no longer carry receptors for signal molecules. 
C) They have exited the cell cycle and entered G0. 
D) They have defective microtubules. 
A) They no longer have active nuclei. 
B) They no longer carry receptors for signal molecules. 
C) They have exited the cell cycle and entered G0. 
D) They have defective microtubules.

Question 6

What will be the result if a eukaryotic cell completes mitosis but does not undergo cytokinesis?

Accepted Answer

A) two cells,one cell containing two nuclei and a second cell without a nucleus 
B) two cells,each cell with half of the genetic material of the parent cell 
C) one cell with two nuclei,each containing half of the genetic material of the parent cell 
D) one cell with one nucleus containing half of the genetic material of the parent cell 
E) one cell with two nuclei,each identical to the nucleus of the parent cell 
A) two cells,one cell containing two nuclei and a second cell without a nucleus 
B) two cells,each cell with half of the genetic material of the parent cell 
C) one cell with two nuclei,each containing half of the genetic material of the parent cell 
D) one cell with one nucleus containing half of the genetic material of the parent cell 
E) one cell with two nuclei,each identical to the nucleus of the parent cell

Question 7

-In the figure above,which numbered segment(s)of the cycle would include cells at some phase of mitosis?

Accepted Answer

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

Question 8

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.

Question 9

Which of the following components make(s)up eukaryotic chromatin?

Accepted Answer

A) condensed DNA only 
B) DNA and RNA 
C) DNA and carbohydrates 
D) DNA and proteins 
E) DNA and ribosomes 
A) condensed DNA only 
B) DNA and RNA 
C) DNA and carbohydrates 
D) DNA and proteins 
E) DNA and ribosomes

Question 10

-In the figure above,which numbered segment(s)of the cycle would contain cells at metaphase of mitosis?

Accepted Answer

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

Question 11

Which of the following molecules or structures 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 12

Where do the microtubules of the spindle originate during mitosis in animal cells?

Accepted Answer

A) centromere 
B) centrosome 
C) centriole 
D) chromatid 
E) kinetochore 
A) centromere 
B) centrosome 
C) centriole 
D) chromatid 
E) kinetochore

Question 13

The unlettered circle at the top of the figure above 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.What is the correct chromosomal condition for a nucleus in G1 of the cell division cycle?

Accepted Answer

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

Question 14

When a cell is in late anaphase of mitosis,which of the following may be observed?

Accepted Answer

A) a clear area in the center of the dividing cell 
B) decondensing chromosomes clustered at the poles 
C) individual chromatids beginning to separate from one another 
D) chromosomes clustered tightly at the center of the dividing cell 
E) nuclear envelopes forming at the poles 
A) a clear area in the center of the dividing cell 
B) decondensing chromosomes clustered at the poles 
C) individual chromatids beginning to separate from one another 
D) chromosomes clustered tightly at the center of the dividing cell 
E) nuclear envelopes forming at the poles

Question 15

Several organisms,including some diatoms and yeasts,have intermediate mitotic organization.Which of the following is the most probable hypothesis regarding these intermediate forms of cell division?

Accepted Answer

A) They represent a form of cell reproduction that must have evolved completely separately from that present in most eukaryotes. 
B) These species are not closely related other diatoms and yeasts,even though they may be similar in outward appearance. 
C) They rely on totally different proteins for the processes they undergo. 
D) They show some but not all of the evolutionary steps toward complete mitosis. 
A) They represent a form of cell reproduction that must have evolved completely separately from that present in most eukaryotes. 
B) These species are not closely related other diatoms and yeasts,even though they may be similar in outward appearance. 
C) They rely on totally different proteins for the processes they undergo. 
D) They show some but not all of the evolutionary steps toward complete mitosis.

Question 16

-In the figure above,which numbered segment(s)of the cycle represent DNA synthesis?

Accepted Answer

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

Question 17

You have the technology necessary to measure each of the following in a sample of animal cells: carbohydrates,organelle density,picograms of DNA,cell wall components,and enzymatic activity.Which of the following cell characteristics would you expect to increase significantly between a cell in mitosis and one just beginning G1?

Accepted Answer

A) organelle density 
B) cell wall components 
C) DNA content 
D) enzyme activity 
E) carbohydrates 
A) organelle density 
B) cell wall components 
C) DNA content 
D) enzyme activity 
E) carbohydrates

Question 18

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

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 19

Following DNA replication,each eukaryotic chromosome consists of two identical DNA molecules known as

Accepted Answer

A) daughter chromosomes 
B) sister chromatids 
C) sister cohesins 
D) sister chromatins 
A) daughter chromosomes 
B) sister chromatids 
C) sister cohesins 
D) sister chromatins

Question 20

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.

Exam 9: The Cell Cycle

Beginning with a fertilized egg (zygote),how many cells would be present in an embryo following a series of five cell divisions?

If the cell whose nuclear material is shown in the figure above continues toward completion of mitosis,which of the following events would occur next?

-In the figure above,which numbered segment(s)of the cycle represent the period during which the chromosomes are replicated?

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

Why do most cells in the human body divide infrequently?

What will be the result if a eukaryotic cell completes mitosis but does not undergo cytokinesis?

-In the figure above,which numbered segment(s)of the cycle would include cells at some phase of mitosis?

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?

Which of the following components make(s)up eukaryotic chromatin?

-In the figure above,which numbered segment(s)of the cycle would contain cells at metaphase of mitosis?

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

Where do the microtubules of the spindle originate during mitosis in animal cells?

When a cell is in late anaphase of mitosis,which of the following may be observed?

Several organisms,including some diatoms and yeasts,have intermediate mitotic organization.Which of the following is the most probable hypothesis regarding these intermediate forms of cell division?

-In the figure above,which numbered segment(s)of the cycle represent DNA synthesis?

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

Following DNA replication,each eukaryotic chromosome consists of two identical DNA molecules known as

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?

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

Ecological Communities

Ecosystems and Energy

Conservation Biology and Global Change

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