Question 1

In animals, which of the following statements describes one difference between reproductive cloning and therapeutic cloning?

Accepted Answer

A)  Reproductive cloning uses totipotent cells, whereas therapeutic cloning does not. 
B)  Reproductive cloning uses embryonic stem cells, whereas therapeutic cloning does not. 
C)  Therapeutic cloning uses nuclei of adult cells transplanted into enucleated nonfertilized eggs, whereas reproductive cloning does not. 
D)  Therapeutic cloning supplies cells that may treat disease, whereas reproductive cloning supplies cells that may be used to produce new individuals. 
A)  Reproductive cloning uses totipotent cells, whereas therapeutic cloning does not. 
B)  Reproductive cloning uses embryonic stem cells, whereas therapeutic cloning does not. 
C)  Therapeutic cloning uses nuclei of adult cells transplanted into enucleated nonfertilized eggs, whereas reproductive cloning does not. 
D)  Therapeutic cloning supplies cells that may treat disease, whereas reproductive cloning supplies cells that may be used to produce new individuals. D

Question 2

Absence of bicoid mRNA from a Drosophila egg leads to the absence of anterior larval body parts and mirror-image duplication of posterior parts. This is evidence that the product of the bicoid gene

Accepted Answer

A)  normally leads to formation of head structures. 
B)  normally leads to formation of tail structures. 
C)  is transcribed in the early embryo. 
D)  is a protein present in all head structures. 
A)  normally leads to formation of head structures. 
B)  normally leads to formation of tail structures. 
C)  is transcribed in the early embryo. 
D)  is a protein present in all head structures. A

Question 3

Forms of the Ras protein found in tumors usually cause which of the following?

Accepted Answer

A)  DNA replication to be hyperactive 
B)  cell-to-cell adhesion to be nonfunctional 
C)  cell division to stop 
D)  growth factor signaling to be hyperactive 
A)  DNA replication to be hyperactive 
B)  cell-to-cell adhesion to be nonfunctional 
C)  cell division to stop 
D)  growth factor signaling to be hyperactive D

Question 4

The product of the bicoid gene in Drosophila provides essential information about

Accepted Answer

A)  lethal genes. 
B)  the dorsal-ventral axis. 
C)  segmentation. 
D)  the anterior-posterior axis. 
A)  lethal genes. 
B)  the dorsal-ventral axis. 
C)  segmentation. 
D)  the anterior-posterior axis.

Question 5

Apoptosis involves all but which of the following?

Accepted Answer

A)  fragmentation of the DNA 
B)  cell-signaling pathways 
C)  lysis of the cell 
D)  digestion of cellular contents by scavenger cells 
A)  fragmentation of the DNA 
B)  cell-signaling pathways 
C)  lysis of the cell 
D)  digestion of cellular contents by scavenger cells

Question 6

The bicoid gene product is normally localized to the anterior end of the embryo. If large amounts of the product were injected into the posterior end as well, which of the following would occur?

Accepted Answer

A)  The embryo would grow to an unusually large size. 
B)  The embryo would grow extra wings and legs. 
C)  The embryo would probably show no anterior development and die. 
D)  Anterior structures would form in both sides of the embryo. 
A)  The embryo would grow to an unusually large size. 
B)  The embryo would grow extra wings and legs. 
C)  The embryo would probably show no anterior development and die. 
D)  Anterior structures would form in both sides of the embryo.

Question 7

If a Drosophila female has a homozygous mutation for a maternal effect gene,

Accepted Answer

A)  she will not develop past the early embryonic stage. 
B)  all of her offspring will show the mutant phenotype, regardless of their genotype. 
C)  only her male offspring will show the mutant phenotype. 
D)  her offspring will show the mutant phenotype only if they are also homozygous for the mutation. 
A)  she will not develop past the early embryonic stage. 
B)  all of her offspring will show the mutant phenotype, regardless of their genotype. 
C)  only her male offspring will show the mutant phenotype. 
D)  her offspring will show the mutant phenotype only if they are also homozygous for the mutation.

Question 8

Which of the following statements correctly describes one of the differences between embryonic and adult stem cells in animals?

Accepted Answer

A)  Embryonic stem cells can differentiate into more cell types than adult stem cells. 
B)  Adult stem cells can differentiate into more cell types than embryonic stem cells. 
C)  Embryonic stem cells have fewer genes than adult stem cells. 
D)  Embryonic stem cells are localized to specific sites within the embryo, whereas adult stem cells are spread throughout the body. 
A)  Embryonic stem cells can differentiate into more cell types than adult stem cells. 
B)  Adult stem cells can differentiate into more cell types than embryonic stem cells. 
C)  Embryonic stem cells have fewer genes than adult stem cells. 
D)  Embryonic stem cells are localized to specific sites within the embryo, whereas adult stem cells are spread throughout the body.

Question 9

The cancer-causing forms of the Ras protein are involved in which of the following processes?

Accepted Answer

A)  activation of protein kinases 
B)  DNA replication 
C)  DNA repair 
D)  activation of apoptosis 
A)  activation of protein kinases 
B)  DNA replication 
C)  DNA repair 
D)  activation of apoptosis

Question 10

Which of the following statements is true of embryonic stem cells?

Accepted Answer

A)  They normally differentiate into only eggs and sperm. 
B)  They can give rise to all cell types in the organism. 
C)  They can continue to reproduce for an indefinite period. 
D)  They can provide enormous amounts of information about the process of gene regulation. 
A)  They normally differentiate into only eggs and sperm. 
B)  They can give rise to all cell types in the organism. 
C)  They can continue to reproduce for an indefinite period. 
D)  They can provide enormous amounts of information about the process of gene regulation.

Question 11

Mutations in which of the following genes lead to transformations in the identity of entire body parts?

Accepted Answer

A)  morphogens 
B)  segmentation genes 
C)  egg-polarity genes 
D)  homeotic genes 
E)  inducers 
A)  morphogens 
B)  segmentation genes 
C)  egg-polarity genes 
D)  homeotic genes 
E)  inducers

Question 12

Which of the following statements is a likely explanation for why therapeutic cloning is considered acceptable by many?

Accepted Answer

A)  Use of adult stem cells is likely to produce more cell types than use of embryonic stem cells. 
B)  Cloning to produce embryonic stem cells may lead to treatments for a large number of diseases. 
C)  Cloning to produce stem cells relies on a different initial procedure than reproductive cloning. 
D)  A clone that lives until the blastocyst stage does not yet have human DNA. 
E)  No embryos would be destroyed in the process of therapeutic cloning. 
A)  Use of adult stem cells is likely to produce more cell types than use of embryonic stem cells. 
B)  Cloning to produce embryonic stem cells may lead to treatments for a large number of diseases. 
C)  Cloning to produce stem cells relies on a different initial procedure than reproductive cloning. 
D)  A clone that lives until the blastocyst stage does not yet have human DNA. 
E)  No embryos would be destroyed in the process of therapeutic cloning.

Question 13

The fact that plants can be cloned from somatic cells demonstrates that

Accepted Answer

A)  differentiated cells retain all the genes of the zygote. 
B)  genes are lost during differentiation. 
C)  the differentiated state is normally very unstable. 
D)  differentiated cells contain masked mRNA. 
E)  differentiation does not occur in plants. 
A)  differentiated cells retain all the genes of the zygote. 
B)  genes are lost during differentiation. 
C)  the differentiated state is normally very unstable. 
D)  differentiated cells contain masked mRNA. 
E)  differentiation does not occur in plants.

Question 14

A genetic test to detect predisposition to cancer would likely examine the APC gene for involvement in which type(s) of cancer?

Accepted Answer

A)  colorectal 
B)  lung and breast 
C)  small intestinal and esophageal 
D)  lung only 
A)  colorectal 
B)  lung and breast 
C)  small intestinal and esophageal 
D)  lung only

Question 15

Proto-oncogenes can change into oncogenes that cause cancer. Which of the following best explains the presence of these potential time bombs in eukaryotic cells?

Accepted Answer

A)  Proto-oncogenes first arose from viral infections. 
B)  Proto-oncogenes are mutant versions of normal genes. 
C)  Proto-oncogenes are genetic "junk." 
D)  Proto-oncogenes normally help regulate cell division. 
A)  Proto-oncogenes first arose from viral infections. 
B)  Proto-oncogenes are mutant versions of normal genes. 
C)  Proto-oncogenes are genetic "junk." 
D)  Proto-oncogenes normally help regulate cell division.

Question 16

What is considered to be the first evidence of differentiation in the cells of an embryo?

Accepted Answer

A)  cell division occurring after fertilization 
B)  the occurrence of mRNAs for the production of tissue-specific proteins 
C)  determination of specific cells for certain functions 
D)  changes in the size and shape of the cell 
E)  changes resulting from induction 
A)  cell division occurring after fertilization 
B)  the occurrence of mRNAs for the production of tissue-specific proteins 
C)  determination of specific cells for certain functions 
D)  changes in the size and shape of the cell 
E)  changes resulting from induction

Question 17

Which of the following is characteristic of the product of the p53 gene?

Accepted Answer

A)  It is an activator for other genes. 
B)  It slows down the cell cycle. 
C)  It does not cause cell death via apoptosis. 
D)  It slows down the rate of DNA replication by interfering with the binding of DNA polymerase. 
A)  It is an activator for other genes. 
B)  It slows down the cell cycle. 
C)  It does not cause cell death via apoptosis. 
D)  It slows down the rate of DNA replication by interfering with the binding of DNA polymerase.

Question 18

Which of the following problems with animal cloning might result in premature death of the clones?

Accepted Answer

A)  use of pluripotent instead of totipotent stem cells 
B)  abnormal gene regulation due to variant methylation 
C)  the indefinite replication of totipotent stem cells 
D)  abnormal immune function due to bone marrow dysfunction 
A)  use of pluripotent instead of totipotent stem cells 
B)  abnormal gene regulation due to variant methylation 
C)  the indefinite replication of totipotent stem cells 
D)  abnormal immune function due to bone marrow dysfunction

Question 19

Why are the BRCA1 and BRCA2 genes considered to be tumor-suppressor genes?

Accepted Answer

A)  They prevent infection by tumor viruses that cause cancer. 
B)  Their normal products participate in repair of DNA damage. 
C)  The mutant forms of either one of these prevent breast cancer. 
D)  They block penetration of breast cells by chemical carcinogens. 
A)  They prevent infection by tumor viruses that cause cancer. 
B)  Their normal products participate in repair of DNA damage. 
C)  The mutant forms of either one of these prevent breast cancer. 
D)  They block penetration of breast cells by chemical carcinogens.

Question 20

Muscle cells differ from nerve cells mainly because they

Accepted Answer

A)  express different genes. 
B)  contain different genes. 
C)  use different genetic codes. 
D)  have unique ribosomes. 
A)  express different genes. 
B)  contain different genes. 
C)  use different genetic codes. 
D)  have unique ribosomes.

Exam 16: Development, Stem Cells, and Cancer

In animals, which of the following statements describes one difference between reproductive cloning and therapeutic cloning?

Absence of bicoid mRNA from a Drosophila egg leads to the absence of anterior larval body parts and mirror-image duplication of posterior parts. This is evidence that the product of the bicoid gene

Forms of the Ras protein found in tumors usually cause which of the following?

The product of the bicoid gene in Drosophila provides essential information about

Apoptosis involves all but which of the following?

The bicoid gene product is normally localized to the anterior end of the embryo. If large amounts of the product were injected into the posterior end as well, which of the following would occur?

If a Drosophila female has a homozygous mutation for a maternal effect gene,

Which of the following statements correctly describes one of the differences between embryonic and adult stem cells in animals?

The cancer-causing forms of the Ras protein are involved in which of the following processes?

Which of the following statements is true of embryonic stem cells?

Mutations in which of the following genes lead to transformations in the identity of entire body parts?

Which of the following statements is a likely explanation for why therapeutic cloning is considered acceptable by many?

The fact that plants can be cloned from somatic cells demonstrates that

A genetic test to detect predisposition to cancer would likely examine the APC gene for involvement in which type(s) of cancer?

Proto-oncogenes can change into oncogenes that cause cancer. Which of the following best explains the presence of these potential time bombs in eukaryotic cells?

What is considered to be the first evidence of differentiation in the cells of an embryo?

Which of the following is characteristic of the product of the p53 gene?

Which of the following problems with animal cloning might result in premature death of the clones?

Why are the BRCA1 and BRCA2 genes considered to be tumor-suppressor genes?

Muscle cells differ from nerve cells mainly because they

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

The Cell Cycle

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

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

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