The presence of what group differentiates most amino acids from each other?

1 answer:

6 0

Amino acids are the basic structural unit of all proteins. A 'free' amino acid (a single amino acid) always has:
an amino group -NH2,
a carboxyl group -COOH
a hydrogen -H
a chemical group or side chain -"R".
Since the amino acids (except glycine) have 4 different groups attached to the a-carbon, they are optically active stereoisomers (recall 23.101 Organic Chemistry) although only L-isomers are found in proteins.
At a neutral pH, both the amino and the carboxyl groups are ionised, giving what is termed the zwitterionic

You might be interested in

An action potential traveling along the entire length of an axon demonstrates ________ propagation.

Rudik [331]

An action potential traveling along the entire length of an axon demonstrates continuous propagation.

Propagation of action potential:

An action potential is created by the rapid input of Na+ ions and the slightly slower outflow of K+ ions.
Action potential initiation occurs in the axon's first segment, and as action potentials spread throughout the axon, cells can convey their output to synapses located further distant from the cell.
The action potential conducts continuously in unmyelinated axons, whereas it conducts rapidly and saltatorily in myelinated axons where sodium channels are concentrated near the nodes of Ranvier.
The action potential always advances in the same direction whenever a local current begins to form due to the prior axon segment still being in the absolute refractory period. As a result, action potentials travel away from the location of their generation and do not change course.