Amino acids are the monomers of proteins. each amino acid consists of a carbon atom bound to a hydrogen atom, an amino group (-nh2), a carboxyl group (-cooh), and a variable r group. which functional group acts as an acid?

The -COOH group of the protein molecule act as acid .

Explanation:

According to Arrhenius law the substance that can donate proton in an aqueous solution is known as acid.

    From this point of view it can the stated that the carboxylic group -COOH act as acid because -COOH group donates proton in aqueous solution and exist as COO-.Thus -COOH group of a protein molecule act as an acid.

a

explanation:

hey bro i looked it up on google the structure of the eye-spot in euglena viridie, e. ehrenbergii, and phacus pyriyorme is not as franzé haa described it. the so-called “crystal body” and “lens bodies” were not found in any of the individuals of the species examined by me. as earlier observers have stated, the eye-spot consists simply of a mass of pigment granules arranged in a single layer, and probably embedded in a protoplasmic framework, but the latter could not be seen, and its presence was only inferred from the fact that the pigment granules must be held together in some way, thd the eye-spot as a whole is capable of expansion, and that the pigment granules can be separated from each other.

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