Question

please i want computer typing answer

2. Why is histidine considered to have good buffering capacity under physiological conditions?

Answer 1

Histidine is a amino acid.It has three ionisable group.

1.carboxyl group

2.amino group

3.imidazole group

The amino group is responsible for the observed pKa value of 6.12 and the imidazole group responsible for the pKa of 9.45.

importent :

* The pKa of histidine is 6.0 , so histidine is best buffer at pH 6.0.because that histidine is the only amino acid with pH 7.4 within its buffering range,such that histidine is the best amino acid buffer under physiological condition.