Exam 3 Review

Question 1

How might a single base insertion into the second codon of the codon sequence of a gene affect the amino acid sequence of a protein encoded by the gene?

Answer 1

The amino acid sequence would be altered

Question 2

Which type of mutation converts a nucleotide to an alternative structure with the same composition but a slightly different placement of rare, less stable hydrogen bonds that cause base-pair mismatch?

Answer 2

tautomeric shift

Question 3

An intercalating agent such as aflatoxin is more likely to cause which type of mutation?

Answer 3

frameshift

Question 4

Which of the following statements is true of non-homologous end joining(NHEJ)?

Answer 4

-it is a double-strand repair pathway
-it is error-prone

Question 5

In an allopolyploid organism, what is true regarding the fertility of interspecies hybrids?

Answer 5

Chromosome doubling and nondisjunction in gametocytes can lead to homologous chromosome pairing, disjunction, and fertile hybrids

Question 6

Heterozygous carriers of chromosome inversions or translocations_____?

Answer 6

-may or may not exhibit phenotypic abnormalities
-may be infertile due to complications during meiosis

Question 7

A region of a chromosome on spanning the centromere is broken and reattached in the reverse direction. This is an example of which type of chromosomal defect?

Answer 7

pericentric inversion

Question 8

A chromosome has broken, and a piece of one chromosome is translocated to a non-homologous chromosome. This is an example of what type of chromosomal alteration?

Answer 8

unbalanced translocation

Question 9

Alul is an example of which type of transposable element commonly found in the genome of humans?

Answer 9

SINE elements

Question 10

Monosomic genome means a genome missing a copy of one chromosome. Which of the following represents monosomic?

Answer 10

2n-1

Question 11

What is a major cause of aneuploidy?

Answer 11

Nondisjunction

Question 12

Which of the following is NOT a transition mutation?

Answer 12

A–>C

Question 13

What ploidy level does 3n=36 represent?

Answer 13

Triploid

Question 14

Human males introduce more point mutations (base substitutions) than females into human gene pool. Is this true or false?

Answer 14

True

Question 15

Chromosomal aberrations occur at a lower frequency than spontaneous mutations in humans. This statement is_____?

Question 16

Down syndrome is caused by ____?

Answer 16

chromosome aberration

Question 17

What is a close approximation of spontaneous mutation rate in human?

Answer 17

10E-9

Question 18

Which aspect of population genetics refers to chance fluctuations of allele frequencies resulting from sampling error and is more prominent in small, isolated population?

Answer 18

gene drift

Question 19

In a group of 500 people, the frequency of genotype NN is 40%. Assuming both autosomal inheritance and that the population is in hardy-weinberg equilibrium, how many individuals would you expect to have the MN genotype?

Answer 19

252

Question 20

Which of the following best predicts the response of a trait to artificial selection?

Answer 20

h^2