Answer:
A. The tails do not interact with the DNA
Explanation:
The acetylation refers to the transfer of the acetyl group from Acetyl-CoA to the N-terminal of the histone protein.
Lysine residues (positively charged amino acid) are present at the end of the N-terminal of the histone protein which is neutralized by the acetyl group.
This loses the compaction between the positively charged histone and the negatively charged DNA and the DNA becomes more relaxed. This relaxed state allows the transcription factors to easily bind the DNA and therefore the DNA becomes transcriptionally active.
Thus, Option-A is correct
The answer u r looking for is- D* failure of the immune system to distinguish self from nonself. Hope I’ve helped ;)
Answer:
D. 1 BB : 2 Bb : 1 bb
Explanation:
This question involves a single gene coding for fur color in guinea pig. Black fur (B) is dominant over white fur (b). This means that, as stated in the question, if a black fur parent (BB) is crossed with a white fur parent (bb), a 100% heterozygous offspring (Bb) with black fur will result.
If two heterozygous guinea pigs are crossed i.e. Bb × Bb, the following gametes will be produced by each heterozygous parent:
Bb = B and b
Using these gametes in a punnet square (see attached image), offsprings with the following genotypic ratio will be produced:
1 BB : 2 Bb : 1 bb
BB and Bb = black fur guinea pigs
bb = white fur guinea pigs
The mutation will occur on the X chromosome. Males are more susceptible to sickle cell amenia because they only carry one X chromosome instead of two when compared to a set of female chromosomes. If a female only has the mutation on one chromosome the disease will not appear. However, when a male recieves the mutation on the X chromosome, the disease would appear, because they only have one X chromosome.
