1. What would be the result of a cytosine base being substituted for a thymine base in a DNA segment during DNA replication?
A. The sequence could code for the wrong amino acid during translation.
B. There would be no effect on the DNA.
C. The cytosine base would pair with adenine when the DNA was replicated.
D. The entire segment of DNA would be affected.
2. Which statement is the first step of protein synthesis?
A. Amino acids are linked together with peptide bonds.
B. DNA unzips between the base pairs.
C. tRNA carries amino acids to the ribosome and attaches them to the mRNA strand.
D. A ribosome attaches to the mRNA.
3. Which statement is true?
A. The human body uses 20 amino acids to form all types of proteins.
B. tRNA is attached to specific proteins in the cell's cytoplasm.
C. Amino acids do not need to be assembled in a particular order.
D. Amino acids form a polypeptide chain via carbon-carbon bonds.
4. Which statement about cystic fibrosis is true?
A. Cystic fibrosis is caused by a deletion of one codon in the DNA molecule.
B. Cystic fibrosis affects a person's ability to make normal red blood cells.
C. Cystic fibrosis is caused by a mutation in which a dominant allele replaces a recessive allele.
D. Carriers have an advantage over people who do not have the cystic fibrosis mutation.
5. What benefit does using the CRISPR technique have in creating GMOs?
A. Precise traits can be chosen to produce viable organisms more quickly.
B. It eliminates all risk of mutation.
C. CRISPR can result in infertile hybrids.
D. Diversity within species can continue to increase through crossbreeding.
6. What is the phenotype of a mouse that has the genotype Bb where B is the gene for black fur and b is the gene for brown fur assuming this gene follows a Mendelian inheritance pattern?
A. Fur with brown hairs
B. Fur with both black and brown hairs.
C. Fur with yellow hairs
D. Fur with black hairs
7. A tall, heterozygous pea plant is crossed with another tall, heterozygous pea plant. What is the probability that an offspring will be a short plant?
A. 0%
B. 25%
C. 75%
D. 50%
8. Which of the following mutations would be most likely to have a harmful effect on an organism?
A. All mutations have a harmful effect on organisms.
B. A substitution of a thymine for an adenine.
C. A deletion of 3 bases near the center of a gene.
D. There is not enough information to know whether a mutation would be harmful.
9. Which statement best describes why Punnett squares are useful?
A. Punnett squares are used to predict the most likely allele combinations of the parents in a cross.
B. Punnett squares are used to predict all possible allele combinations and their frequencies in offspring.
C. Punnett squares are used to predict how recessive alleles are inherited.
D. Punnett squares are used to predict how dominant alleles are inherited.
11. How are new viruses made?
A. viral DNA or RNA copied by viral cells.
B. viral DNA or RNA copied by a host cell.
C. asexual reproduction
D. sexual reproduction
12. Compare and contrast a provirus and viral DNA.
A. A provirus is newly replicated viral DNA after injection.
B. A provirus is viral DNA incorporated into the host cell's DNA.
C. A provirus is bacterial DNA incorporated into the viral DNA.
D. A provirus is the host cell's DNA that has been destroyed.
13. Why is the common cold virus difficult to cure in humans?
A. It is caused by a special type of virus called a retrovirus.
B. It is a spherical-shaped virus with many protein receptors.
C. It possesses a viral genome that mutates very quickly.
D. It attacks white blood cells that fight off foreign bodies.
14. What function makes the HIV virus unique?
A. It attacks neurons in the nervous system and causes paralysis.
B. It has viral DNA that is transmitted through indirect contact with infected persons.
C. It attacks and destroys red blood cells in the bodies of its host organisms.
D. It copies the information for reproduction from RNA back into DNA.
1. C. The cytosine base would pair with adenine when the DNA was replicated, leading to a change in the DNA sequence.
2. B. DNA unzips between the base pairs.
3. A. The human body uses 20 amino acids to form all types of proteins.
4. C. Cystic fibrosis is caused by a mutation in which a dominant allele replaces a recessive allele.
5. A. Precise traits can be chosen to produce viable organisms more quickly.
6. D. Fur with black hairs.
7. B. 25%.
8. C. A deletion of 3 bases near the center of a gene.
9. A. Punnett squares are used to predict the most likely allele combinations of the parents in a cross.
11. B. viral DNA or RNA copied by a host cell.
12. B. A provirus is viral DNA incorporated into the host cell's DNA.
13. C. It possesses a viral genome that mutates very quickly.
14. D. It copies the information for reproduction from RNA back into DNA.