Biological Sciences Questions, Part 2

11. Define the following terms:

a. DNA
b. Gene
c. Locus

12. Briefly explain the term isomer and identify an example of an isomer.

13. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

By applying information included in the passage, a person with cystic fibrosis must have:

A. Two working CTFR genes.
B. One working CTFR gene and one faulty gene.
C. One working CTFR gene and one completely nonworking gene.
D. Two CTFR genes that are not working correctly.

14. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area the near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

By applying the information included in the passage, a person without cystic fibrosis must have:

A. One dominant CTFR gene and one recessive CTFR gene
B. Two dominant CTFR genes
C. Two recessive CTFR genes
D. They can have options A or B

15. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

By applying the information included in the passage, an individual with cystic fibrosis must have parents that:

A. Both have two dominant genes.
B. Both have at least one recessive gene.
C. One has one recessive gene, but the other has two dominant genes.
D. Have cystic fibrosis.

16. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

By applying the information included in the passage, the likelihood that a child will inherit cystic fibrosis if his or her parents each have one recessive gene is approximately:

A. 1 in 4 (25%)
B. 2 in 4 (50%)
C. 3 in 4 (75%)
D. 4 in 4 (100%)

17. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

By applying the information included in the passage, the likelihood that a child will inherit cystic fibrosis if his or her parents both have cystic fibrosis is approximately:

A. 1 in 4 (25%)
B. 2 in 4 (50%)
C. 3 in 4 (75%)
D. 4 in 4 (100%)

18. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

The word "autosomal" refers to the fact that the recessive gene is found on:

A. Chromosomes that are not related to determining the individual's gender.
B. Chromosomes that are related to determining the individual's gender.
C. Chromosomes that are mutated.
D. Chromosomes that are damaged.

19. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

The word "mutation" refers to the fact that:

A. The base pair of the DNA sequence for the gene has been altered.
B. The gene is constantly changing.
C. The DNA sequence is exactly the way it should be.
D. A gene has malfunctioned and therefore created a harmful condition.

20. Cystic fibrosis, which is sometimes referred to as CF for short, is one of the most common autosomal recessive genetic diseases found in individuals of European descent. The disease actually occurs due to a mutation of the cystic fibrosis transmembrane conductance regulator also known as the CTFR gene. Most individuals have two functioning CTFR genes that produce proteins that act as ion channels in a variety of tissues throughout the body. Each of these tissues manufactures fluids such as digestive enzymes, mucus, and sweat. However, this mutation causes the CTFR gene to manufacture its proteins incorrectly so the proteins disintegrate before they are able to reach the area near the cell membrane, which causes the water, salt, and other materials attempting to move in and out of the cell to become blocked.

The water and salt buildup mentioned in the passage leads to thick mucous secretions that would likely:

A. Block airways and glands.
B. Cause sinus infections.
C. Cause damage to vital organs.
D. All of the above.




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