Imagine that you have created a fusion between the Trp operon, which encodes the enzymes for tryptophan biosynthesis, and the Lac operon, which encodes the enzymes necessary for lactose utilization. Under which set of conditions (A–F below) will β-galactosidase be expressed in the strain that carries the fused operon?

A. Only when lactose and glucose are both absent.

B. Only when lactose and glucose are both present.

C. Only when lactose is absent and glucose is present.

D. Only when lactose is present and glucose is absent.

E. Only when tryptophan is absent.

F. Only when tryptophan is present.

TLS Online TPP Program

#Question id: 28669

#Unit 2. Cellular Organization

Fission yeast cells carrying a CDK1 mutation in which the tyrosine-15 residue is replaced by phenylalanine, what will cause from this mutation?

a) Shows larger than normal cells

b) Shows smaller than normal cells

c) allows the phosphorylation of phenylalanine and normal cell activation are seen

d) premature mitotic CDK activation and entry into mitosis

TLS Online TPP Program

#Question id: 28670

#Unit 2. Cellular Organization

In fission yeast cells carrying a CDK1 mutation in which the tyrosine-15 residue is replaced by other amino acid which is?

TLS Online TPP Program

#Question id: 28671

#Unit 2. Cellular Organization

 In which of the following condition premature mitotic CDK activation and premature entry into mitosis are seen? 

a) during the activity of dual-specificity phosphatases

b) during replacing the tyrosine-15 residue from phenylalanine

c) defective wee1+ gene

TLS Online TPP Program

#Question id: 28672

#Unit 2. Cellular Organization

Which proteins is involved to inhibit Cdc25 phosphatase and hold it into inactive condition

TLS Online TPP Program

#Question id: 28673

#Unit 2. Cellular Organization

Which protein activity involve to facilitate the activating an initial small pool of cyclin B/1 at the centrosome and also facilitate centrosome Maturation?

TLS Online TPP Program

#Question id: 28674

#Unit 2. Cellular Organization

Which of the following cyclin-CDKs involve to phosphorylate Cdc25C for the stimulation of its phosphatase activity ?