Answer: A. Nitrogen
Explanation: Nucleic acids contain the same elements as proteins: carbon, hydrogen, oxygen, nitrogen; plus phosphorous (C, H, O, N, and P). Nucleic acids are very large macromolecules composed of repetitive units of the same building blocks, nucleotides, similar to a pearl necklace made of many pearls.
Answer: Mutualism
Explanation:
Mutualism is a symbiotic relationship in which both interacting species receives the benefit for togetherness.
In the given situation, the birds are receiving food in the form of ticks and the rhinoceros are receiving protection against the predatory blood sucking ticks.
The nervous system and the integumentary system<span />
The answer that best fits the blank provided above is C3a and C5a. Mast cells release this so called histamines once they are exposed to C3a and C5a which are fragments of complement proteins. These are also called as <span>Anaphylatoxins along with C4a. Hope this helps.</span>
The notable
hardness of bone is attributed to the presence of inorganic hydroxyapatites.
Due to the calcium salts deposited in it, resulting to the hardness. The
abnormal hardness of bone, which allows it
to resist the compression.
