Question 1: How does a genetic mutation occur?

Question 1: How does a genetic mutation occur?

a. Base pairs are deleted or inserted along the DNA.

b. The nucleus signals for a mutation to occur.

c. Introns are removed from the genetic sequence.

d. Genetic mutations occur systematically.

Question 2: Why does a genetic abnormality affect protein synthesis?

a. The genetic sequence controls the expression of genes.

b. Nucleotide sequences create proteins.

c. Protein synthesis does not respond to change during expression.

d. Correct genetic sequences determine the assembly of proteins.

Question 3: How does a mutation in the CFTR gene affect membrane transport of a cell in people with cystic fibrosis?

a. The membrane becomes more permeable to ions.

b. Faulty channels cannot transport chloride ions across the membrane.

c. The membrane becomes less permeable to all ions.

d. Membrane transport becomes more selective.

Question 4: Why is genetic screening important?

a. Genetic screening predicts the lifespan of a child.

b. Genetic screening is only important in determining the sex of a child.

c. Genetic screening can determine whether a child has cystic fibrosis.

d. Genetic screening provides information about the genotype of an embryo.

Question 5: Genetic screening of fertilized eggs prior to uterine implantation is a preventative measure that can reduce the number of children born with cystic fibrosis. Such procedures are likely to raise medical, social, and ethical issues about genetic screening. Which is a potential result of increasing the use of genetic screening for serious and life-threatening disorders such as cystic fibrosis?

a. Cystic fibrosis will continue to increase in the gene pool.

b. Genetic disorders may never be eliminated.

c. These issues may result in required genetic screening for all genetic disorders.

d. All genetic disorders will have similar medical issues but different social and ethical issues.

Question 6: Suppose scientists observe homologues and chromatids failing to separate in meiosis I and meiosis II, resulting in nondisjunction. During what phase(s) of gamete formation would scientists first observe this?

a. anaphase I and anaphase II

b. metaphase I and anaphase II

c. telophase II

d. metaphase I

Question 7: A group of students recreated one of the early biologists' experiments using radioactive markers to label DNA and protein. Instead of phosphorus-32 (32P), these students used a radioactive marker to label hydrogen bonds found within the bases of the DNA structure. The students simulated the experimental procedures of which scientist(s)?

a. Watson and Crick

b. Rosalind Franklin

c. Hershey and Chase

d. Gregor Mendel

Question 8: How does RNA polymerase choose which strand to start to use as a template?

a. RNA can only transcribe from the strand with the most major units.

b. Certain sequences called promoter regions determine where transcription begins.

c. RNA can only transcribe from the strand with a high percentage of adenine bases.

d. Certain strands are parent strands and will not allow transcription.

Question 9: A scientist observes a culture of cells dividing with radioactive guanine for several hours. Next, she removes the radioactive guanine and replaces it with nonradioactive guanine. She samples each generation for four generations and measures the radioactivity of each. If the initial DNA was 100 percent radioactive, which would be an example of the percentage of radioactivity for semi-conservative replication of DNA over four generations (G = Generation)?

a. G1 = 100% G2 = 75% G3 = 50% G4 = 25%

b. G1 = 100% G2 = 40% G3 = 25 % G4 = 10 %

c. G1 = 50% G2 = 25% G3 = 12.5% G4 = 6.25%

d. G1 = 50% G2 = 40% G3 = 30% G4 = 20%

Question 10: Which organism undergoes sexual reproduction?

a. paramecium

b. yeast

c. C. elegans

d. flatworm

Question 11: Which enzyme allows for transcription of the RNA strand into a DNA strand of nucleotides?

a. DNA polymerase

b. reverse transcriptase

c. DNA transcriptase

d. helicase

Question 12: In which way is the organization of DNA in prokaryotes and eukaryotes similar?

a. The origin of replication in prokaryotes occurs as frequently as in eukaryotes.

b. They use the same enzymes in DNA replication.

c. Their DNA is arranged in a single helix and makes use of the same nucleotides.

d. They contain extra small circular DNA molecules known as plasmids.

Question 13: Which process is involved in cell and tissue repair?

a. apoptosis

b. meiosis

c. endocytosis

d. mitosis

Question 14: Suppose all the offspring of a white hen and a black roster are grey. What is the simplest explanation for this pattern of inheritance?

a. linkage

b. sex-linked traits

c. incomplete dominance

d. independent assortment

Question 15: Eye color in Drosophila is an X-linked trait. What is the probability that a father with red eyes will have children that inherit his red eyes?

a. 1/4

b. 1/2

c. 1/8

d. 1/16

Question 16: What level of structural organization of a protein forms hydrogen bonds in the backbone of the polypeptide chain?

a. tertiary structure

b. secondary structure

c. primary structure

d. quaternary structure

Question 17: Each year Hillary cuts several stalks off her grandmother's aloe vera plant to give to students in her class when discussing the benefits of aloe vera. Hillary hopes that the students will grow an aloe vera plant of their own from each stalk. What form of asexual reproduction would this be an example of?

a. budding

b. fragmentation

c. parthenogenesis

d. gametogenesis

Question 18: Which statement is an example of Mendel's contribution to the scientific understanding of inheritance?

a. Mendel established the principles of transmission genetics.

b. Mendel showed that unit factors, called alleles, exist alone.

c. Mendel postulated that unit factors must integrate during gamete formation.

d. Mendel described the presence of linked genes.

Question 19: The discovery of DNA's double helix structure provides justification for which phenomenon?

a. equal ratios of adenine to guanine and thymine to cytosine

b. semi-conservative replication of DNA

c. the formation of disulfide bonds between base pairs

d. that DNA is the genetic material

Question 20: Which phase of meiosis best supports the law of segregation and independent assortment?

a. prophase

b. telophase

c. metaphase

d. anaphase

Question 21: Which represents the gametes of a plant of with genotype RrWw ?

a. RR and WW

b. RW and rw

c. RW, Rw, rW, and rw

d. RR, rr, WW, and ww

Question 22: Suppose two parents that are sickle-cell anemia carriers have children. What is the probability that their offspring will be carriers of sickle cell, but not afflicted with the disease?

a. 25%

b. 75%

c. 50%

d. 33%

Question 23: In pea plants, allele A is dominant over allele a, and allele B is dominant over allele b. Parents that are homozygous dominant for both traits are crossed with a parents that are homozygous recessive for both traits. The offspring of this cross are then crossed. What is the probability that an offspring of the second generation will be AaBb? (Express your answer as the simplest fraction.)

Question 24: In pea plants, the allele for yellow seeds (Y) is dominant over the one for green seeds (y) and the allele for round seeds (R) is dominant over the one for wrinkled seeds (r). A homozygous yellow, round seed is crossed with a homozygous green, wrinkled seed. The offspring of this cross are then crossed. What is the probability that an offspring of the second generation will be green and wrinkled? (Express your answer as the simplest fraction.)