Chapter 4: Genes and Genetic Diseases

Chapter 4: Genes and Genetic Diseases

 

Complete Chapter Questions With Answers

 

Sample Questions Are Posted Below

 

MULTIPLE CHOICE

 

1. Inserting bone marrow cells into an individual who produces abnormal erythrocytes is an example of what type of therapy?

a.	Somatic cell	c.	Genetic engineering
b.	Germ cell	d.	Recombinant DNA

 

 

ANS:  A

Gene therapy can be applied in two ways. The less controversial approach is somatic cell therapy, which consists of inserting normal genes into the cells of an individual who has a genetic disease. In this approach, a particular tissue, such as bone marrow cells that produce abnormal erythrocytes, is treated. The correct option is the only one that accurately identifies the therapy described in the question.

 

PTS:   1                    REF:   Page 137 | Box 4-2

 

2. DNA replication requires the enzyme DNA polymerase to:

a.	Travel along the single DNA strand, adding the correct nucleotide to the new strand
b.	Move along the double strand of DNA to unwind the nucleotides of the double helix
c.	Hold the double strand apart while the correct nucleotides are added to the strand
d.	Transport the double strand of DNA from the nucleus to the cytoplasm for protein formation

 

 

ANS:  A

The DNA polymerase enzyme travels along the single DNA strand, adding the correct nucleotides to the free end of the new strand (see Figure 4-2, B). The correct option is the only one that accurately describes the process involved in DNA replication using DNA polymerase.

 

PTS:   1                    REF:   Page 137

 

3. Transcription is best defined as a process by which:

a.	DNA polymerase binds to the promoter site on ribonucleic acid (RNA).
b.	RNA directs the synthesis of polypeptides for protein synthesis.
c.	RNA is synthesized from a DNA template.
d.	A base pair substitution results in a mutation of the amino acid sequence.

 

 

ANS:  C

Transcription is the process by which RNA is synthesized from a DNA template. The correct option is the only one that accurately defines the term transcription.

 

PTS:   1                    REF:   Page 141

 

4. The purpose of a staining technique of chromosomes such as Giemsa is to:

a.	Permit the mitotic process to be followed and monitored for variations.
b.	Allow for the numbering of chromosomes and the identification of variations.
c.	Identify new somatic cells formed through mitosis and cytokinesis.
d.	Distinguish the sex chromosomes from the homologous chromosomes.

 

 

ANS:  B

One of the most commonly used stains is Giemsa stain. By using banding techniques, chromosomes can be unambiguously numbered, and individual variation in chromosome composition can be studied. Missing or duplicated portions of chromosomes, which often result in serious diseases, also can be readily identified. The correct option is the only one that accurately describes the purpose of the Giemsa staining technique.

 

PTS:   1                    REF:   Pages 142-143

 

5. An amniocentesis indicates a neural tube defect when an increase in which protein is evident?

a.	Chorionic	c.	Amniotic
b.	Alpha fetoprotein	d.	Embryonic

 

 

ANS:  B

Other disorders can be detected with this procedure. These include most neural tube defects, which cause an elevation of alpha fetoprotein in the amniotic fluid, and hundreds of diseases caused by mutations of single genes. The correct option is the only one that accurately identifies the protein responsible for a neural tube defect.

 

PTS:   1                    REF:   Page 136 | Box 4-1