Question 1

Which of the following statements correctly describes chromatin?

Accepted Answer

A)  Heterochromatin is composed of DNA, whereas euchromatin is made of DNA and RNA. 
B)  Both heterochromatin and euchromatin are found in the cytoplasm. 
C)  Heterochromatin is highly condensed, whereas euchromatin is less compact. 
D)  Euchromatin is not transcribed, whereas heterochromatin is transcribed. 
A)  Heterochromatin is composed of DNA, whereas euchromatin is made of DNA and RNA. 
B)  Both heterochromatin and euchromatin are found in the cytoplasm. 
C)  Heterochromatin is highly condensed, whereas euchromatin is less compact. 
D)  Euchromatin is not transcribed, whereas heterochromatin is transcribed.

Question 2

Please use the following information to answer the question(s) below.
A group of six students has taken samples of their own cheek cells, purified the DNA, and used a restriction enzyme known to cut at zero, one, or two sites in a particular gene of interest.
-Why might they be conducting such an experiment?

Accepted Answer

A)  to find the location of this gene in the human genome 
B)  to prepare to isolate the chromosome on which the gene of interest is found 
C)  to find which of the students has which alleles 
D)  to collect population data that can be used to assess natural selection 
A)  to find the location of this gene in the human genome 
B)  to prepare to isolate the chromosome on which the gene of interest is found 
C)  to find which of the students has which alleles 
D)  to collect population data that can be used to assess natural selection

Question 3

Polytene chromosomes of Drosophila salivary glands each consist of multiple identical DNA strands that are aligned in parallel structures. How could these arise?

Accepted Answer

A)  replication followed by mitosis 
B)  replication without separation 
C)  meiosis followed by mitosis 
D)  fertilization by multiple sperm 
E)  special association with histone proteins 
A)  replication followed by mitosis 
B)  replication without separation 
C)  meiosis followed by mitosis 
D)  fertilization by multiple sperm 
E)  special association with histone proteins

Question 4

Please use the following information to answer the question(s) below.
A eukaryotic gene has "sticky ends" produced by the restriction endonuclease EcoRI. The gene is added to a mixture containing EcoRI and a bacterial plasmid that carries two genes conferring resistance to the antibiotics ampicillin and tetracycline. The plasmid has one recognition site for EcoRI located in the tetracycline resistance gene. This mixture is incubated for several hours, exposed to DNA ligase, and then added to bacteria growing in nutrient broth. The bacteria are allowed to grow overnight and are streaked on a plate using a technique that produces isolated colonies that are clones of the original. Samples of these colonies are then grown in four different media: nutrient broth plus ampicillin, nutrient broth plus tetracycline, nutrient broth plus ampicillin and tetracycline, and nutrient broth without antibiotics.
-Bacteria that contain the plasmid, but not the eukaryotic gene, would grow

Accepted Answer

A)  in the nutrient broth plus ampicillin, but not in the broth containing tetracycline. 
B)  only in the broth containing both antibiotics. 
C)  in the broth containing tetracycline, but not in the broth containing ampicillin. 
D)  in all four types of broth. 
E)  in the nutrient broth without antibiotics only. 
A)  in the nutrient broth plus ampicillin, but not in the broth containing tetracycline. 
B)  only in the broth containing both antibiotics. 
C)  in the broth containing tetracycline, but not in the broth containing ampicillin. 
D)  in all four types of broth. 
E)  in the nutrient broth without antibiotics only.

Question 5

Figure 13.1
-  Figure 13.4
The segment of DNA shown in Figure 13.4 has restriction sites I and II, which create restriction fragments A, B, and C. Which of the gels produced by electrophoresis shown below best represents the separation and identity of these fragments?

Accepted Answer

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

Question 6

Figure 13.1
-In the late 1950s, Meselson and Stahl grew bacteria in a medium containing "heavy" nitrogen (15N) and then transferred them to a medium containing 14N. Which of the results in Figure 13.1 would be expected after one round of DNA replication in the presence of 14N?

Accepted Answer

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

Question 7

In E. coli, there is a mutation in a gene called dnaB that alters the helicase that normally acts at the origin. Which of the following would you expect as a result of this mutation?

Accepted Answer

A)  No proofreading will occur. 
B)  The DNA strands at the origin of replication will separate, but replication will not progress. 
C)  The DNA will supercoil. 
D)  Replication will require a DNA template from another source. 
A)  No proofreading will occur. 
B)  The DNA strands at the origin of replication will separate, but replication will not progress. 
C)  The DNA will supercoil. 
D)  Replication will require a DNA template from another source.

Exam 13: The Molecular Basis of Inheritance

Which of the following statements correctly describes chromatin?

Polytene chromosomes of Drosophila salivary glands each consist of multiple identical DNA strands that are aligned in parallel structures. How could these arise?

Figure 13.1 - Figure 13.4 The segment of DNA shown in Figure 13.4 has restriction sites I and II, which create restriction fragments A, B, and C. Which of the gels produced by electrophoresis shown below best represents the separation and identity of these fragments?

Figure 13.1 -In the late 1950s, Meselson and Stahl grew bacteria in a medium containing "heavy" nitrogen (15N) and then transferred them to a medium containing 14N. Which of the results in Figure 13.1 would be expected after one round of DNA replication in the presence of 14N?

In E. coli, there is a mutation in a gene called dnaB that alters the helicase that normally acts at the origin. Which of the following would you expect as a result of this mutation?

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

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

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