Question 1

Mutations in the p53 gene can lead to cancer by

Accepted Answer

A) causing the production of excessive amounts of relay proteins. 
B) causing the production of a faulty protein that is no longer able to inhibit cell division. 
C) promoting the expression of mRNA that can interact with DNA, resulting in new mutations. 
D) increasing the production of growth hormones, which trigger faster cell cycles. 
A) causing the production of excessive amounts of relay proteins. 
B) causing the production of a faulty protein that is no longer able to inhibit cell division. 
C) promoting the expression of mRNA that can interact with DNA, resulting in new mutations. 
D) increasing the production of growth hormones, which trigger faster cell cycles.

Question 2

Two yeast cells, one of type a and the other type α, are in proximity to each other. The a yeast cell has a mutation in the gene for the α factor receptor protein such that the receptor does not translocate to the surface of the a cell. If both cells secrete their respective a and α factors, which of the following outcomes is most likely to occur?

Accepted Answer

A) The a and α cells will grow toward each other. 
B) The a cell will grow towards the α cell. 
C) The α cell will grow toward the a cell. 
D) The a and α cells will not grow toward each other at all. 
A) The a and α cells will grow toward each other. 
B) The a cell will grow towards the α cell. 
C) The α cell will grow toward the a cell. 
D) The a and α cells will not grow toward each other at all.

Question 3

The cloning of Dolly the sheep

Accepted Answer

A) demonstrated that the nuclei from differentiated mammalian cells can retain their full genetic potential. 
B) demonstrated that differentiated cells contain only a fraction of their full genetic potential. 
C) demonstrated, for the first time, that eggs are haploid and body cells are diploid. 
D) revealed that cloned mammals most resemble the egg donor. 
A) demonstrated that the nuclei from differentiated mammalian cells can retain their full genetic potential. 
B) demonstrated that differentiated cells contain only a fraction of their full genetic potential. 
C) demonstrated, for the first time, that eggs are haploid and body cells are diploid. 
D) revealed that cloned mammals most resemble the egg donor.

Question 4

In multicellular organisms, the coordination of cellular activities relies on

Accepted Answer

A) cell receptors that detect transcription factors. 
B) the availability of certain "key" nutrients as cells divide. 
C) operons. 
D) cell-to-cell signaling and signal transduction pathways. 
A) cell receptors that detect transcription factors. 
B) the availability of certain "key" nutrients as cells divide. 
C) operons. 
D) cell-to-cell signaling and signal transduction pathways.

Question 5

Small pieces of RNA that can regulate translation of mRNA are called

Accepted Answer

A) microRNA. 
B) interfering RNA. 
C) transfer RNA. 
D) messenger RNA. 
A) microRNA. 
B) interfering RNA. 
C) transfer RNA. 
D) messenger RNA.

Question 6

Scientists are attempting to make a chicken look like a dinosaur ("dino-chicken")by using drugs or proteins to turn on certain homeotic genes during the development of a chicken embryo. If the scientists are successful in creating both male and female "dino-chickens," and then the "dino-chickens" mate together, what type of offspring would the two "dino-chickens" have?

Accepted Answer

A) a male or female "dino-chicken" 
B) a male or female normal chicken 
C) You can't know for sure because of random fertilization. 
D) You can't know for sure because it depends on whether the modified homeotic genes are dominant or recessive. 
A) a male or female "dino-chicken" 
B) a male or female normal chicken 
C) You can't know for sure because of random fertilization. 
D) You can't know for sure because it depends on whether the modified homeotic genes are dominant or recessive.

Question 7

A cell is expressing the mutant form of ras, but one of the downstream relay proteins is not present because of another mutation. How will cell division be affected in this scenario?

Accepted Answer

A) Cell division will decrease because the mutant form of ras decreases cell division. 
B) Cell division will increase because the mutant form of ras increases cell division. 
C) The cell will divide normally. 
D) The cell will not divide at all unless other proteins that stimulate cell division are present. 
A) Cell division will decrease because the mutant form of ras decreases cell division. 
B) Cell division will increase because the mutant form of ras increases cell division. 
C) The cell will divide normally. 
D) The cell will not divide at all unless other proteins that stimulate cell division are present.

Question 8

Which of the following mammals has not yet been cloned and brought through the complete gestation cycle?

Accepted Answer

A) cow 
B) human 
C) pig 
D) cat 
A) cow 
B) human 
C) pig 
D) cat

Question 9

The lac operon of E. coli is ________ when the repressor is bound to lactose.

Accepted Answer

A) active 
B) inactive 
C) cloned 
D) unregulated 
A) active 
B) inactive 
C) cloned 
D) unregulated

Question 10

All of the following mechanisms are used to regulate protein production except

Accepted Answer

A) protein activation. 
B) protein breakdown. 
C) DNA replication. 
D) the breakdown of mRNA. 
A) protein activation. 
B) protein breakdown. 
C) DNA replication. 
D) the breakdown of mRNA.

Question 11

After reading the paragraph below, answer the questions that follow.
While DNA microarrays can be used to determine whether or not a gene is expressed in a cell, quantitative polymerase chain reaction (qPCR) can be used to measure the extent of gene expression in cells and tissues. To perform qPCR, mRNA is extracted from cells and reverse transcribed to complementary DNA (cDNA). Using fluorescent DNA molecules that recognize specific gene sequences and DNA polymerase, copies of the gene sequence of interest are made. After the copies are made, a fluorescent detector measures the intensity of the fluorescent signal, which is proportional to the number of mRNA transcripts in the cell and corresponds to the level of gene expression in the cell.
-A scientist hypothesizes that a new drug turns on a certain gene in a skin cell. Which of the following experiments would be the best to test her hypothesis?

Accepted Answer

A) Use qPCR to measure the initial levels of gene expression in skin cells, treat skin cells with the drug and measure the levels of gene expression, and then compare the two measurements. 
B) Use qPCR to measure the levels of gene expression in skin cells after exposure to the drug. 
C) Use qPCR to measure the initial levels of gene expression in muscle cells, treat skin cells with the drug and measure the levels of gene expression, and then compare the two measurements. 
D) Use qPCR to measure the levels of gene expression in skin cells after exposure to the drug and then add another drug to turn off gene expression and use qPCR to measure the levels of expression. 
A) Use qPCR to measure the initial levels of gene expression in skin cells, treat skin cells with the drug and measure the levels of gene expression, and then compare the two measurements. 
B) Use qPCR to measure the levels of gene expression in skin cells after exposure to the drug. 
C) Use qPCR to measure the initial levels of gene expression in muscle cells, treat skin cells with the drug and measure the levels of gene expression, and then compare the two measurements. 
D) Use qPCR to measure the levels of gene expression in skin cells after exposure to the drug and then add another drug to turn off gene expression and use qPCR to measure the levels of expression.

Question 12

To initiate a signal transduction pathway, a signal binds to a receptor protein usually located in the

Accepted Answer

A) nucleus. 
B) plasma membrane. 
C) ER. 
D) cytoplasm. 
A) nucleus. 
B) plasma membrane. 
C) ER. 
D) cytoplasm.

Question 13

The expression of the tryptophan operon is controlled by

Accepted Answer

A) a repressor that is active when it is alone. 
B) a repressor that is inactive when it binds to lactose. 
C) a repressor that is active when it binds to tryptophan. 
D) an activator that turns the operon on by binding to DNA. 
A) a repressor that is active when it is alone. 
B) a repressor that is inactive when it binds to lactose. 
C) a repressor that is active when it binds to tryptophan. 
D) an activator that turns the operon on by binding to DNA.

Question 14

Which of the following statements regarding DNA packing is false?

Accepted Answer

A) A nucleosome consists of DNA wound around a protein core of eight histone molecules. 
B) DNA packing tends to promote gene expression. 
C) Highly compacted chromatin is generally not expressed at all. 
D) Prokaryotes have proteins analogous to histones. 
A) A nucleosome consists of DNA wound around a protein core of eight histone molecules. 
B) DNA packing tends to promote gene expression. 
C) Highly compacted chromatin is generally not expressed at all. 
D) Prokaryotes have proteins analogous to histones.

Question 15

The term "gene expression" refers to the

Accepted Answer

A) fact that each individual of a species has a unique set of genes. 
B) fact that individuals of the same species have different phenotypes. 
C) process by which genetic information flows from genes to proteins. 
D) flow of information from parent to offspring. 
A) fact that each individual of a species has a unique set of genes. 
B) fact that individuals of the same species have different phenotypes. 
C) process by which genetic information flows from genes to proteins. 
D) flow of information from parent to offspring.

Question 16

The basis of cellular differentiation is

Accepted Answer

A) the operon. 
B) selective gene expression. 
C) cloning. 
D) mutation. 
A) the operon. 
B) selective gene expression. 
C) cloning. 
D) mutation.

Question 17

The genes for the enzymes of glycolysis

Accepted Answer

A) are active in all metabolizing cells, but the genes for specialized proteins are expressed only in particular cell types. 
B) are inactive in all metabolizing cells, but the genes for specialized proteins are expressed in all cell types. 
C) and the genes for all specialized proteins are expressed in all metabolizing cells. 
D) and the genes for all specialized proteins are expressed in all embryonic cells. 
A) are active in all metabolizing cells, but the genes for specialized proteins are expressed only in particular cell types. 
B) are inactive in all metabolizing cells, but the genes for specialized proteins are expressed in all cell types. 
C) and the genes for all specialized proteins are expressed in all metabolizing cells. 
D) and the genes for all specialized proteins are expressed in all embryonic cells.

Question 18

Which of the following is not a factor that contributes to normal cells becoming cancerous?

Accepted Answer

A) the conversion of a proto-oncogene to an oncogene 
B) damage to a tumor-suppressor gene 
C) the production of more effective tumor-suppressor gene products 
D) excessive replication of proto-oncogenes 
A) the conversion of a proto-oncogene to an oncogene 
B) damage to a tumor-suppressor gene 
C) the production of more effective tumor-suppressor gene products 
D) excessive replication of proto-oncogenes

Question 19

The development of colon cancer occurs slowly, and colon cancer is more frequently seen in the elderly than the young. This is most likely because

Accepted Answer

A) cancer cells don't have mitochondria, so they grow slowly. 
B) usually six or more somatic mutations must occur to give rise to the cancer, which takes time. 
C) cancer cells have to wait until new blood vessels grow into the area, which takes much time. 
D) most cancer mutations interfere with mitosis, so cell division occurs more slowly. 
A) cancer cells don't have mitochondria, so they grow slowly. 
B) usually six or more somatic mutations must occur to give rise to the cancer, which takes time. 
C) cancer cells have to wait until new blood vessels grow into the area, which takes much time. 
D) most cancer mutations interfere with mitosis, so cell division occurs more slowly.

Question 20

Why can some plants be cloned from a single cell?

Accepted Answer

A) Plant cells do not differentiate even when mature, so any cell can grow into an entire plant. 
B) Plant cells can dedifferentiate and give rise to all of the specialized cells required to produce an entire plant. 
C) Plant cells can produce genes to replace those lost during development. 
D) Plant cells are capable of self-renewal by utilizing cellular components from adjacent cells. 
A) Plant cells do not differentiate even when mature, so any cell can grow into an entire plant. 
B) Plant cells can dedifferentiate and give rise to all of the specialized cells required to produce an entire plant. 
C) Plant cells can produce genes to replace those lost during development. 
D) Plant cells are capable of self-renewal by utilizing cellular components from adjacent cells.

Exam 11: How Genes Are Controlled

Mutations in the p53 gene can lead to cancer by

The cloning of Dolly the sheep

In multicellular organisms, the coordination of cellular activities relies on

Small pieces of RNA that can regulate translation of mRNA are called

A cell is expressing the mutant form of ras, but one of the downstream relay proteins is not present because of another mutation. How will cell division be affected in this scenario?

Which of the following mammals has not yet been cloned and brought through the complete gestation cycle?

The lac operon of E. coli is ________ when the repressor is bound to lactose.

All of the following mechanisms are used to regulate protein production except

To initiate a signal transduction pathway, a signal binds to a receptor protein usually located in the

The expression of the tryptophan operon is controlled by

Which of the following statements regarding DNA packing is false?

The term "gene expression" refers to the

The basis of cellular differentiation is

The genes for the enzymes of glycolysis

Which of the following is not a factor that contributes to normal cells becoming cancerous?

The development of colon cancer occurs slowly, and colon cancer is more frequently seen in the elderly than the young. This is most likely because

Why can some plants be cloned from a single cell?

Biology: Exploring Life

The Chemical Basis of Life

The Molecules of Cells

A Tour of the Cell

The Working Cell

How Cells Harvest Chemical Energy

Photosynthesis: Using Light to Make Food

The Cellular Basis of Reproduction and Inheritance

Patterns of Inheritance

Molecular Biology of the Gene

DNA Technology and Genomics

How Populations Evolve

The Origin of Species

Tracing Evolutionary History

Microbial Life: Prokaryotes and Protists

The Evolution of Plant and Fungal Diversity

The Evolution of Invertebrate Diversity

The Evolution of Vertebrate Diversity

Unifying Concepts of Animal Structure and Function

Nutrition and Digestion

Gas Exchange

Circulation

the Immune System

Control of Body Temperature and Water Balance

Hormones and the Endocrine System

Reproduction and Embryonic Development

Nervous Systems

the Senses

How Animals Move

Plant Structure, Growth, and Reproduction

Plant Nutrition and Transport

Control Systems in Plants

the Biosphere: an Introduction to Earths Diverse Environments

Behavioral Adaptations to the Environment

Population Ecology

Communities and Ecosystems

Conservation Biology

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