False because <span>Like DNA, RNA is assembled as a chain of </span>nucleotides<span>, but unlike DNA it is more often found in nature as a single-strand folded onto itself, rather than a paired double-strand. Cellular organisms use </span>messenger RNA<span> (</span>mRNA<span>) to convey genetic information.</span>
Answer:
The microscopic structural unit of compact bone is called an osteon, or Haversian system. Each osteon is composed of concentric rings of calcified matrix called lamellae (singular = lamella).
Explanation:
Because it is the main site for digestion. food is totally digested and absorbed in small intestine so it is long.
The earthworm has a closed circulatory system, and there are 3 main vessels: <span>aortic arches, dorsal blood vessels, and ventral blood vessels.
aortic arches: It functions as the heart of the earthworm
dorsal blood vessels: Responsible to carry blood to the front of the body
ventral blood vessels: Responsible to carry blood to the back of the body
hope this helps</span>
Answer:
Three nucleotide
Explanation:
Three nucleotides are required to code for one amino acid. There are four types of nucleotides A, T, G, C which make DNA. So a doublet of nucleotide code which involves only two nucleotide would be insufficient to code for 20 amino acids because if 4 different nucleotide is taken two at a time then it can only produce 16 amino acid(4²=16).
But if we take three-nucleotide than the number reaches 64 which is more than sufficient to code for 20 different amino acids(4³= 64). Therefore 3 nucleotides are needed to code for an amino acid.
