Question

In trp operon, the presence of Tryptophan _____ the genes in the operon. a) Represses b)Activates...

In trp operon, the presence of Tryptophan _____ the genes in the operon.

a) Represses

b)Activates

c)Mutates

D)Does not change

2)In lac operon, it is safe to say that the presence of glucose would have _____ effect on the transcription of the genes in the operon.

a)enhancing

b)repressive

C)no

3)

A human cell in metaphase II of a meiosis cell cycle is ______

a)Triploid

B)Haploid

C)Tetraploid

D)Diploid

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Homework Answers

Answer #1

Answer (1)(a)Represses

Explanation-

In tryptophan operon, tryptophan repressor inactive in native form and tryptophan acts as Co-repressor so it binds to repressor protein and makes him active.This active repressor binds at operator region so RNA polymerase can't bind at promoter region so transcription of tryptophan operon genes repressed.

Answer (2)(b)repressive

Explanation-

When Glucose is present in the medium then cAMP level very low so CAP dimer can't formed because in presence of cAMP CAP dimer formed.

CAP dimer is necessary for the proper positioning of RNA polymerase so when Glucose is present,RNA polymerase proper positioning can't occur so transcription of lac operon genes repressed.

Answer (3)(B)Haploid

A human cell in metaphase II of a meiosis cell cycle is Haploid because it contains 23 Chromosomes in Metaphase ll

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