Answer :
There are 9 amino acids that cannot be naturally synthesized.
Histidine
Isoleucine
Lysine
Methionine
Phenylalanine
Theronine
Tryptophan
Valine
Hope it helps!
Histidine
Isoleucine
Lysine
Methionine
Phenylalanine
Theronine
Tryptophan
Valine
Hope it helps!