Answer:
D) presence of transcription activators or repressors
Explanation:
The reason why this is not post-transcriptional regulation is that activators actually start the process of transcription by binding to specific sites. while on contrary when repressor binds it halt the process.
For example, there is a protein called CAP which in the presence of cAMP bind with promoter region and enhances the activity of RNA polymerase . While in the absence of cAMP it can not bind to promoter hence the transcription stooped.
Answer:
Option (e).
Explanation:
Meiosis may be defined as the process of cell division in which a single parent cell divides into four daughter cells. The chromosome number reduces to half in meiosis.
Crossing over is the process of exchange of genetic material between the homologous chromosomes of the non-sister chromatids. Crossing over will bring variation in the gametes. Hence, the absence of crossing over results in the formation of gametes with less genetic variation.
Thus, the correct answer is option (e).
Answer:b. The earth has warmed 10 times faster than it did coming out of the last Ice Age
Explanation: global warming from environmental degredation.