Biochemistry

Question 1

what is the only amino acid that is achiral?

Answer 1

glycine; it does not have 4 different groups attached the the alpha carbon

Question 2

what is the only amino acid with an R configuration?

Answer 2

cysteine

Question 3

are the amino acids found in eukaryotes L or D conformation?

Answer 3

L

Question 4

will a majority of the species be protonated or deprotonated if the pH is less than the pKa?

Answer 4

protonated

Question 5

will a majority of the species be protonated or deprotonated if the pH is greater than the pKa?

Answer 5

deprotonated

Question 6

at very low pH, do amino acids tend to be positively or negatively charged?

Answer 6

positive

Question 7

what is the pKa of the carboxyl group of an amino acid?

Answer 7

2

Question 8

what is the pKa of the amino group of an amino acid?

Answer 8

9-10

Question 9

pKa

Answer 9

pH at which a species is 50% protonated and 50% deprotonated

Question 10

pH > pKa =

Answer 10

deprotonation

Question 11

pH < pKa =

Answer 11

protonation

Question 12

at very high pH, do amino acids tend to be positively or negatively charged?

Answer 12

negative

Question 13

is the species more likely to be positive or negative at acidic conditions?

Answer 13

positive

Question 14

is the species more likely to be positive or negative at basic conditions?

Answer 14

negative