Biology Chapter 15

Diploid somatic cells of elephants have 56 chromosomes. If nondisjunction of one of an elephant's chromosomes occurs in meiosis II, the resulting sperm are expected to have the chromosome complement: A. 28, 28, 28, 28 B. 28, 28, 29, 27 C. 29, 29, 27, 27 D. 29, 29, 28, 28 E. 56, 56, 57, 55

B

Are all point mutations SNPs? A. Yes, because SNPs are single base pair changes of the DNA. B. Yes, because SNPs are random in their occurrence. C. No, because SNPs require a certain frequency in the population. D. No, because SNPs are mismatched base pairs.

C

Diploid somatic cells of elephants have 56 chromosomes. If nondisjunction of one of an elephant's chromosomes occurs in meiosis I, the resulting sperm are expected to have the chromosome complement: A. 28, 28, 28, 28 B. 28, 28, 29, 27 C. 29, 29, 27, 27 D. 29, 29, 28, 28 E. 56, 56, 57, 55

C

Nondisjunction of X chromosomes may occur during meiosis 1 of oogenesis to form 2 types of eggs. If normal sperm fertilize these two types of egg, which of the following are possible sex chromosome complements? A. XX and XY B. XYY and XO C. XYY and YO D. XXY and XO E. XXX and XYY

D

The phenotype of an individual results from an interaction between: A. Allele frequency and mutation rate. B. Allele frequency and genotype. C. Genotype and mutation rate. D. Genotype and the environment. E. Allele frequency and the environment.

D

Ultraviolet light is a mutagen, but humans need some exposure to it to synthesize vitamin D. The amount of ultraviolet light that penetrates the skin depends on the skin's pigmentation: more melanin (skin pigment) means less penetration. Certain mutations result in decreased melanin production. Such mutations: A. Are harmful only if inherited from both parents. B. Are beneficial only if inherited from both parents. C. Are neutral only if inherited from one parent, not the other. D. May be harmful in one environment and beneficial in another.

D

When DNA with variable number tandem repeats (VNTRs) is amplified by PCR and visualized on a gel, the resulting fragments separate according to their: A. A-T content. B. G-C content. C. Color. D. Size. E. Shape.

D

Why does data on observable mutant phenotypes underestimate the actual frequency of mutation? A. Many mutations are in non-coding regions of the genome. B. Some mutations in protein coding regions of the genome are synonymous or silent mutations. C. Most mutations result in death of the individual or an inability to reproduce. D. Options 1 and 2 are correct. E. Options 1, 2, and 3 are correct.

D

Which one of the following statements about restriction fragment length polymorphisms (RFLPs) is correct? A. RFLPs are the product of cleavage by restriction enzymes. B. RFLPs are variations in restriction sites that result in DNA being cleaved into different-sized pieces. C. RFLPs are numerous in the human population. D. RFLPs can serve as a genetic fingerprint in forensic analyses. E. All of the answer options are correct.

E