Question 1

Which of the following statements correctly describes the function of a signal peptide?

Accepted Answer

A) It directs an mRNA molecule into the Golgi apparatus. 
B) It causes RNA polymerase to bind DNA and initiate transcription. 
C) It terminates translation of the messenger RNA. 
D) It assists in the translocation of polypeptides across the ER membrane. 
A) It directs an mRNA molecule into the Golgi apparatus. 
B) It causes RNA polymerase to bind DNA and initiate transcription. 
C) It terminates translation of the messenger RNA. 
D) It assists in the translocation of polypeptides across the ER membrane.

Question 2

The nitrogenous base adenine is found in all members of which of the following groups of molecules?

Accepted Answer

A) proteins,triglycerides,and testosterone 
B) proteins,ATP,and DNA 
C) ATP,RNA,and DNA 
D) glucose,ATP,and DNA 
A) proteins,triglycerides,and testosterone 
B) proteins,ATP,and DNA 
C) ATP,RNA,and DNA 
D) glucose,ATP,and DNA

Question 3

-Examine the simple metabolic pathway in the figure above.According to Beadle and Tatum's hypothesis,how many genes are necessary for this pathway?

Accepted Answer

A) 0 
B) 1 
C) 2 
D) 3 
A) 0 
B) 1 
C) 2 
D) 3

Question 4

What must happen to a newly made polypeptide before it can be secreted from a cell?

Accepted Answer

A) It must be translated by a ribosome that remains free of attachment to the ER. 
B) Its signal sequence must target it to the ER,after which it goes to the Golgi. 
C) Its signal sequence must be cleaved off before the polypeptide can enter the ER. 
D) Its signal sequence must target it to the plasma membrane,where it causes exocytosis. 
A) It must be translated by a ribosome that remains free of attachment to the ER. 
B) Its signal sequence must target it to the ER,after which it goes to the Golgi. 
C) Its signal sequence must be cleaved off before the polypeptide can enter the ER. 
D) Its signal sequence must target it to the plasma membrane,where it causes exocytosis.

Question 5

Examine the simple metabolic pathway in the figure above.If A,B,and C are all substances required for growth of the organism that carries out this pathway,a strain that is mutant for the gene encoding enzyme 1 would be able to grow on which of the following media?

Accepted Answer

A) minimal medium 
B) minimal medium supplemented with nutrient A only 
C) minimal medium supplemented with nutrient B only 
D) minimal medium with no supplements 
A) minimal medium 
B) minimal medium supplemented with nutrient A only 
C) minimal medium supplemented with nutrient B only 
D) minimal medium with no supplements

Question 6

What happens to the cut-out intron after alternative RNA splicing?

Accepted Answer

A) It is added back to the mRNA. 
B) It is kept in the nucleus for insertion back into the genomic DNA. 
C) It is transported out of the nucleus for translation in they cytosol. 
D) It is rapidly degraded. 
A) It is added back to the mRNA. 
B) It is kept in the nucleus for insertion back into the genomic DNA. 
C) It is transported out of the nucleus for translation in they cytosol. 
D) It is rapidly degraded.

Question 7

Which of the following is not true of RNA processing?

Accepted Answer

A) Exons are cut out before mRNA leaves the nucleus. 
B) Nucleotides may be added at both ends of the RNA. 
C) Ribozymes may function in RNA splicing. 
D) RNA splicing can be catalyzed by spliceosomes. 
A) Exons are cut out before mRNA leaves the nucleus. 
B) Nucleotides may be added at both ends of the RNA. 
C) Ribozymes may function in RNA splicing. 
D) RNA splicing can be catalyzed by spliceosomes.

Question 8

Use the following model of a eukaryotic transcript to answer the question.E1-4 refer to the exons,and I1-3 refer to the introns in the pre-mRNA transcript.
5' UTR E1 I1 E2 I2 E3 I3 E4 UTR 3'
Suppose that an induced mutation removes most of the 5' end of the 5' UTR.What might be the result of this removal?

Accepted Answer

A) Removal of the 5' UTR has no effect because the exons remain intact. 
B) Removal of the 5' UTR also removes the 5' cap,so the mRNA may be quickly degraded by hydrolytic enzymes. 
C) The 3' UTR will duplicate,and one copy will replace the 5' end. 
D) The first exon will not be read because I1 will now serve as the UTR. 
A) Removal of the 5' UTR has no effect because the exons remain intact. 
B) Removal of the 5' UTR also removes the 5' cap,so the mRNA may be quickly degraded by hydrolytic enzymes. 
C) The 3' UTR will duplicate,and one copy will replace the 5' end. 
D) The first exon will not be read because I1 will now serve as the UTR.

Question 9

Examine the simple metabolic pathway in the figure above.A mutation results in a defective enzyme 1.Which of the following results would be a consequence of that mutation?

Accepted Answer

A) an accumulation of A and no production of B and C 
B) an accumulation of A and B and no production of C 
C) an accumulation of B and no production of A and C 
D) an accumulation of B and C and no production of A 
A) an accumulation of A and no production of B and C 
B) an accumulation of A and B and no production of C 
C) an accumulation of B and no production of A and C 
D) an accumulation of B and C and no production of A

Question 10

Use the following model of a eukaryotic transcript to answer the question.E1-4 refer to the exons,and I1-3 refer to the introns in the pre-mRNA transcript.
5' UTR E1 I1 E2 I2 E3 I3 E4 UTR 3'
Suppose that exposure to a chemical mutagen results in a change in the sequence that alters the 5' end of intron 1 (I1).Which of the following results might occur?

Accepted Answer

A) loss of the gene product 
B) loss of E1 
C) premature transcriptional termination 
D) inclusion of I1 in the mRNA 
A) loss of the gene product 
B) loss of E1 
C) premature transcriptional termination 
D) inclusion of I1 in the mRNA

Question 11

-Examine the table of codons in the figure above.A peptide has the sequence NH2-phe-pro-lys-gly-phe-pro-COOH.Which of the following sequences in the coding strand of the DNA could code for this peptide?

Accepted Answer

A) 3'-UUU-CCC-AAA-GGG-UUU-CCC 
B) 3'-AUG-AAA-GGG-TTT-CCC-AAA-GGG 
C) 5'-TTT-CCC-AAA-GGG-TTT-CCC 
D) 5'-GGG-AAA-TTT-AAA-CCC-ACT-GGG 
A) 3'-UUU-CCC-AAA-GGG-UUU-CCC 
B) 3'-AUG-AAA-GGG-TTT-CCC-AAA-GGG 
C) 5'-TTT-CCC-AAA-GGG-TTT-CCC 
D) 5'-GGG-AAA-TTT-AAA-CCC-ACT-GGG

Question 12

In which direction does RNA polymerase move along the DNA?

Accepted Answer

A) 5' to 3' along whichever strand it's on 
B) 3' to 5' along the template strand 
C) 5' to 3' along the template strand 
D) 5' to 3' along the double-stranded DNA 
A) 5' to 3' along whichever strand it's on 
B) 3' to 5' along the template strand 
C) 5' to 3' along the template strand 
D) 5' to 3' along the double-stranded DNA

Question 13

A particular triplet of bases in the template strand of DNA is 5'-AGT-3'.The corresponding codon for the mRNA transcribed is

Accepted Answer

A) 3'-UCA-5'. 
B) 3'-UGA-5'. 
C) 5'-TCA-3'. 
D) 3'-ACU-5'. 
A) 3'-UCA-5'. 
B) 3'-UGA-5'. 
C) 5'-TCA-3'. 
D) 3'-ACU-5'.

Question 14

Which of the following DNA mutations is likely to have the most negative effect on the protein it specifies?

Accepted Answer

A) a base-pair deletion 
B) a codon substitution 
C) a substitution in the last base of a codon 
D) a codon deletion 
A) a base-pair deletion 
B) a codon substitution 
C) a substitution in the last base of a codon 
D) a codon deletion

Question 15

A transfer RNA (#1)attached to the amino acid lysine enters the ribosome.The lysine binds to the growing polypeptide on the other tRNA (#2)already in the ribosome.Where does tRNA #2 move to after this bonding of lysine to the polypeptide?

Accepted Answer

A) A site 
B) P site 
C) E site 
D) exit tunnel 
A) A site 
B) P site 
C) E site 
D) exit tunnel

Question 16

Which of the following statements is correct regarding protein synthesis in prokaryotes and eukaryotes?

Accepted Answer

A) Transcription and translation can occur at the same time in both organisms. 
B) Translation can begin while transcription is still in progress in prokaryotes,but not in eukaryotes. 
C) The RNA produced during transcription is then modified in both types of organisms. 
D) In prokaryotes,transcription produces a protein,but in eukaryotes,it produces RNA. 
A) Transcription and translation can occur at the same time in both organisms. 
B) Translation can begin while transcription is still in progress in prokaryotes,but not in eukaryotes. 
C) The RNA produced during transcription is then modified in both types of organisms. 
D) In prokaryotes,transcription produces a protein,but in eukaryotes,it produces RNA.

Question 17

In an experimental situation,a student researcher inserts an mRNA molecule into a eukaryotic cell after she has removed its 5' cap and poly-A tail.Which of the following would you expect her to find?

Accepted Answer

A) The mRNA would not be transported out of the nucleus. 
B) The cell recognizes the absence of the tail and adds a new poly-A tail to the mRNA. 
C) The molecule is digested by restriction enzymes in the nucleus. 
D) The molecule is degraded by hydrolytic enzymes because it is no longer protected at the 5' end and the 3' end. 
A) The mRNA would not be transported out of the nucleus. 
B) The cell recognizes the absence of the tail and adds a new poly-A tail to the mRNA. 
C) The molecule is digested by restriction enzymes in the nucleus. 
D) The molecule is degraded by hydrolytic enzymes because it is no longer protected at the 5' end and the 3' end.

Question 18

Which of the following statements correctly defines the process of gene expression?

Accepted Answer

A) Gene expression is the process by which proteins direct the synthesis of DNA. 
B) Gene expression is the process by which DNA directs the synthesis of proteins. 
C) Gene expression is the process by which proteins direct the synthesis of RNA. 
D) Gene expression is the process by which RNA direct the synthesis of DNA. 
A) Gene expression is the process by which proteins direct the synthesis of DNA. 
B) Gene expression is the process by which DNA directs the synthesis of proteins. 
C) Gene expression is the process by which proteins direct the synthesis of RNA. 
D) Gene expression is the process by which RNA direct the synthesis of DNA.

Question 19

The process of translation in both prokaryotes and eukaryotes requires tRNAs,amino acids,and ribosomal subunits.Which of the following components must also be present for translation to proceed?

Accepted Answer

A) protein factors and ATP 
B) protein factors and GTP 
C) polymerases and GTP 
D) signal peptides plus release factor 
A) protein factors and ATP 
B) protein factors and GTP 
C) polymerases and GTP 
D) signal peptides plus release factor

Question 20

When the genome of a particular species is said to include 20,000 protein-coding regions,what does this imply?

Accepted Answer

A) There are 20,000 genes. 
B) Each gene codes for one protein. 
C) There are also additional genes for RNAs other than mRNA. 
D) The species is highly evolved. 
A) There are 20,000 genes. 
B) Each gene codes for one protein. 
C) There are also additional genes for RNAs other than mRNA. 
D) The species is highly evolved.

Exam 14: Gene Expression: From Gene to Protein

Which of the following statements correctly describes the function of a signal peptide?

The nitrogenous base adenine is found in all members of which of the following groups of molecules?

-Examine the simple metabolic pathway in the figure above.According to Beadle and Tatum's hypothesis,how many genes are necessary for this pathway?

What must happen to a newly made polypeptide before it can be secreted from a cell?

Examine the simple metabolic pathway in the figure above.If A,B,and C are all substances required for growth of the organism that carries out this pathway,a strain that is mutant for the gene encoding enzyme 1 would be able to grow on which of the following media?

What happens to the cut-out intron after alternative RNA splicing?

Which of the following is not true of RNA processing?

Examine the simple metabolic pathway in the figure above.A mutation results in a defective enzyme 1.Which of the following results would be a consequence of that mutation?

-Examine the table of codons in the figure above.A peptide has the sequence NH2-phe-pro-lys-gly-phe-pro-COOH.Which of the following sequences in the coding strand of the DNA could code for this peptide?

In which direction does RNA polymerase move along the DNA?

A particular triplet of bases in the template strand of DNA is 5'-AGT-3'.The corresponding codon for the mRNA transcribed is

Which of the following DNA mutations is likely to have the most negative effect on the protein it specifies?

A transfer RNA (#1)attached to the amino acid lysine enters the ribosome.The lysine binds to the growing polypeptide on the other tRNA (#2)already in the ribosome.Where does tRNA #2 move to after this bonding of lysine to the polypeptide?

Which of the following statements is correct regarding protein synthesis in prokaryotes and eukaryotes?

In an experimental situation,a student researcher inserts an mRNA molecule into a eukaryotic cell after she has removed its 5' cap and poly-A tail.Which of the following would you expect her to find?

Which of the following statements correctly defines the process of gene expression?

The process of translation in both prokaryotes and eukaryotes requires tRNAs,amino acids,and ribosomal subunits.Which of the following components must also be present for translation to proceed?

When the genome of a particular species is said to include 20,000 protein-coding regions,what does this imply?

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

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

Filters

-Examine the table of codons in the figure above.A peptide has the sequence NH₂-phe-pro-lys-gly-phe-pro-COOH.Which of the following sequences in the coding strand of the DNA could code for this peptide?