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).
adverb noun [C]. âº grammar a word that âdescribes or gives more âinformation about another word, esp. a âverb, âadjective, or other adverb, or about a phrase: In the âsentences, She smiled cheerfully and He âwaited âright âoutside the âdoor, cheerfully and âright are adverbs. In â English, adverbs are usually â formed by â adding 'ly' to the end of an â adjective. 2  Today we â learned about adverbs of â manner, â time and â place. 3  A phrasal â verb consists of a â verb in â combination with a â preposition or adverb.