Question

1.Mendel accounted for the observation that traits which had disappeared in the F1 generation reappeared in the F2 generation by proposing that

Group of answer choices

the mechanism controlling the appearance of traits was different between the F1 and the F2 plants.

the traits were lost in the F1 due to blending of the parental traits.

new mutations were frequently generated in the F2 progeny, "reinventing" traits that had been lost in the F1.

traits can be dominant or recessive, and the recessive traits were obscured by the dominant ones in the F1.

2. Caffeine is an inhibitor of the enzyme phosphodiesterase. Therefore, the cells of a person who has recently consumed coffee would have persistently increased levels of

Group of answer choices

None of the answers apply.

IP3

calcium

cAMP

3.An inhibitor of adenylyl cyclase would have which of the following effects?

Group of answer choices

blocks the synthesis of cAMP in the cytoplasm

block the activation of G proteins in response to receptor activation

maintaining elevated cAMP levels in the cytoplasm

increase the response to a hormone

Answer 1

Ans.1) correct answer is traits can be dominant or recessive, and the recessive traits were obscured by the dominant ones in the F1. It can be understood by following example -,

Ans.2) correct answer is there will be increased level of cAMP.

Phosphodiesterase enzyme(PDE) decreases level of cAMP,cGMP by back converting them to ATP and GTP. Caffeine inhibits PDE and thus level of cAMP increases.

Ans.3) correct answer is blocks the synthesis of cAMP in the cytoplasm.

Adenylate cyclase converts ATP into cAMP in cytoplasm, thus increases level of cAMP. Inhibition of Adenylate cyclase will lead to inhibition of cAMP synthesis in Cytoplasm.