Semen by definition is the fluid ejaculated from a male, which includes the sperm cells as well as a number of other components. The Elements (ingredients) Of Semen. Very simply put, seminal fluid is a thick white secretion rich in sugars, mostly fructose to fuel the sperm cells on their journey to the egg. This secretion is what composes the bulk of semen by volume (50-80%). Although mostly comprised of water, proteins, and sugars.
The T-cell receptor, or TCR, is a molecule found on the surface of T cells, or T lymphocytes, that is responsible for recognizing fragments of antigen as peptides bound to major histocompatibility complex (MHC) molecules.
T-cells are essential for human immunity. The devastating effects of a lower than normal number of just one type of T-cell are all too evident in HIV/AIDS. There are several different kinds of T-cell; broadly speaking they can be divided into two different types, killer T-cells and helper T-cells. Killer T-cells have âX-ray visionâ as they are able to see inside our bodies own cells simply by scanning their surface.