The human immunodeficiency virus (HIV) is a lentivirus (a subgroup of retrovirus) that causes HIV infection and acquired immunodeficiency syndrome (AIDS).AIDS is a condition in humans in which progressive failure of the immune system allows life-threatening opportunistic infections and cancers to thrive.he human immunodeficiency virus (HIV) is a lentivirus (a subgroup of retrovirus) that causes HIV infection and acquired immunodeficiency syndrome (AIDS).
The definition of optimal is the most favorable. An example of optimal used as an adjective is in the phrase optimal score, which means the highest score someone can get on a game. most favorable or desirable; best; optimum. Origin of optimal.
Optimum. Definition. noun. The best, the most favorable, the most suitable, or the most advantageous condition or result. Supplement. The word optimum in biology is often used to denote to a condition or a result that is favourable or best for a particular living entity. For instance, the term optimum pH refers to the pH resulting in maximal activity of a particular enzyme. Differing pH levels affect the shape of an enzyme.