Answer:
The CORRECT ANSWER IS B.
B. Unlike the other countercurrent systems, a countercurrent multiplier system expends energy in active transport.
Explanation:
The countercurrent multiplier system involving the loop of Henle uses up energy in the form of ATP to actively conduct NaCl out of the filtrate in the upper region of the ascending limb of the loop. This energy in the form of ATP that is being used uniquely differentiates a countercurrent multiplier system from the different forms of countercurrent systems.
Therefore, a 10x eyepiece used with a 40X objective lens, will produce a magnification of 400X. The naked eye can now view the specimen at a magnification 400 times greater and so microscopic details are revealed. More on objective lenses here. Magnification is the ability to view an object as larger.
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