Biology · Biological Molecules
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Proteins are macromolecules formed of units known as amino acids. The amino acids in which the variable group (R) is represented by a H atom is:
- A
Lysine
- B
Phenylalanine
- C
Glycine
- D
Alanine
Amino acids are organic compounds which contain both an amine group (NH2) and a carboxyl group (COOH). They are distinguished by the attached functional group R (side chain).
In lysine, the R group is represented by (CH2)4NH2. Glycine has the simplest and shortest side chain of all amino acids—its R-group is just a single hydrogen atom. This gives it a small, flexible structure compared to other amino acids.
The R group in phenylalanine can be viewed as a benzyl group (C6H5CH2) substituted for the methyl group of alanine or a phenyl group (C6H5) in place of terminal hydrogen of alanine.
Glycine is the amino acid with the shortest side chain, having an R-group consistent only with a single hydrogen.
The R group of alanine consists of a methyl (CH3) side chain.Glycine has the simplest and shortest side chain of all amino acids—its R-group is just a single hydrogen atom. This gives it a small, flexible structure compared to other amino acids.
Tagged under Biology · Biological Molecules · 2022