On the other hand, essential amino acids are required in the human diet as they cannot be synthesized by the body. There are nine essential amino acids including histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.
The ability to reproduce The ability to respond to stimuli . The 2nd one may be a bit confusing but people who do not respond to stimuli eg they have CIPA or are blind or deaf can still survive
