In the form of proteins, amino acids comprise the second-largest component (water is the largest) of human muscles, cells and other tissues. Outside proteins, amino acids perform critical roles in processes such as neurotransmitter transport and biosynthesis.n biochemistry, amino acids having both the amine and the carboxylic acid groups attached to the first (alpha-) carbon atom have particular importance.
Ad lib redirects here. For other uses, see Ad lib (disambiguation). Ad libitum (/Ã¦dËlÉªbáµ»tÉm/) is Latin for at one's pleasure; it is often shortened to ad lib (as an adjective or adverb) or ad-lib (as a verb or noun).
The meaning of AD is Anno Domini or Year of our Lord referring to the year of Christâs birth. The meaning of BC is Before Christ. CE is a recent term. It refers to Common Era and is used in place of A.D. the dates are the same i.e., 2009 AD is 2009 CE.