Question 1

A plant with genotype $$Ss ($$heterozygous for seed shape) is crossed with a plant with genotype $$ss ($$homozygous recessive for seed shape). What percentage of the offspring will be heterozygous?

Accepted Answer

$$50\%$$

Question 2

Which of the following best explains why there are more X-linked disorders than Y-linked disorders in humans?

Accepted Answer

The X chromosome is larger and contains more genes than the Y chromosome.

Question 3

A woman with type B blood has a child with a man who has type A blood. Which of the following is a possible genotype for the woman?

Accepted Answer

$$I^B i$$

Question 4

If a red flower is crossed with a white flower and all the offspring are pink, which genetic phenomenon best explains this result?

Accepted Answer

Incomplete dominance

Question 5

Which of the following best describes the law of independent assortment as explained by chromosome behavior during meiosis?

Accepted Answer

Homologous chromosomes separate randomly during meiosis I, leading to genetic variation.

Question 6

A color-blind male ($$X^C Y) $$has a child with a woman who is a carrier for color blindness ($$X^N X^C). $$What is the probability that their child will be color-blind?

Accepted Answer

$$50\%$$

Question 7

Which of the following changes in chromosomal structure involves a segment of a chromosome being reversed end to end?

Accepted Answer

Inversion

Question 8

If one DNA strand reads $$3'	ext{-}ACTAG	ext{-}5'$$, what would the complementary DNA strand read?

Accepted Answer

$$5'	ext{-}TGATC	ext{-}3'$$

Question 9

Which functional group defines the $$5'$$ end of a DNA strand?

Accepted Answer

Phosphate group

Question 10

During DNA replication, which enzyme is responsible for unwinding the DNA double helix at the replication fork?

Accepted Answer

Helicase

Question 11

Which process converts DNA to RNA?

Accepted Answer

Transcription

Question 12

Where does translation occur in eukaryotic cells?

Accepted Answer

Cytoplasm

Question 13

Which of the following best describes a silent mutation?

Accepted Answer

A mutation that does not change the amino acid sequence of the protein

Question 14

If a mutation causes the insertion of a single nucleotide in a coding region, what is the most likely effect on the resulting protein?

Accepted Answer

A frameshift mutation, which often leads to a nonfunctional protein

Question 15

Which of the following is true about the genetic code?

Accepted Answer

It is read in groups of three nucleotides called codons.

Question 16

A dihybrid cross between two plants heterozygous for both traits ($$RrWw 	imes RrWw) $$produces 600 offspring. If white color and smooth seeds are both recessive, how many offspring would you expect to be white with smooth seeds?

Accepted Answer

37 or 38

Question 17

Which of the following best describes polygenic inheritance?

Accepted Answer

A single trait is controlled by multiple genes, each contributing to the phenotype.

Question 18

Which enzyme is responsible for joining Okazaki fragments on the lagging strand during DNA replication?

Accepted Answer

DNA ligase

Question 19

Which of the following best describes a test cross?

Accepted Answer

Crossing an individual with a dominant phenotype with a homozygous recessive individual to determine the genotype of the dominant individual.

Question 20

Which of the following is a function of the poly-A tail added to eukaryotic mRNA during processing?

Accepted Answer

It protects mRNA from degradation and assists in export from the nucleus.

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