Some important events in the history of life on Earth are given below.

A. First dinosaurs appeared.

B. First reptiles appeared.

C. First insect fossils appeared.

D. First toothed birds appearance.

E. First wingless insect appeared.

F. Mammals like reptile arise

Match the above with the geological time periods and choose the correct combination,

#Question id: 2666

#SCPH05 I Biotechnology

A cell does not want to waste energy synthesizing the amino acid arginine if arginine is present in its diet. Therefore, when arginine is present, it activates a repressor protein to prevent transcription of genes that code for enzyme to make arginine. This is an example of what type of regulation?

#Question id: 2666

#SCPH06 I Botany

A cell does not want to waste energy synthesizing the amino acid arginine if arginine is present in its diet. Therefore, when arginine is present, it activates a repressor protein to prevent transcription of genes that code for enzyme to make arginine. This is an example of what type of regulation?

#Question id: 2667

#SCPH05 I Biotechnology

A regulatory protein that attracts RNA polymerase to its promoter is an example of what type of regulation?

#Question id: 2667

#SCPH06 I Botany

A regulatory protein that attracts RNA polymerase to its promoter is an example of what type of regulation?

#Question id: 2668

#SCPH05 I Biotechnology

The toxic shock syndrome toxin is produced by some Salmonella species when there is not sufficient iron present. When iron is present, it prevents transcription of the TSS-toxin gene. Iron therefore serves as __________.

#Question id: 2668

#SCPH06 I Botany

The toxic shock syndrome toxin is produced by some Salmonella species when there is not sufficient iron present. When iron is present, it prevents transcription of the TSS-toxin gene. Iron therefore serves as __________.