Question

If the side chain of a glutamic acid residue has a pKa of 4.1, at pH 6.1 the ratio of uncharged to charged side chain would be about
A. 100:1
B. 10:1
C. 1:1
D. 1:10
E. 1:100
-i HAVE NO IDEA


Which of the following amino acids has a side chain that can serve ONLY as a hydrogen bond donor but NOT as a hydrogen bond acceptor in its predominant form at pH 7?
A. N
B. V
C. E
D. K
E. H

-I think this one is D



PLEASE HELP SOMEONE!