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.
The receptors match only one specific antigen. White blood cells called lymphocytes originate in the bone marrow but migrate to parts of the lymphatic system such as the lymph nodes, spleen, and thymus. There are two main types of lymphatic cells, T cells and B cells. cells can also produce memory cells with an even longer life span than B memory cells. The second time an intruder tries to invade the body, B and T memory cells help the immune system to activate much faster. The invaders are wiped out before the infected human feels any symptoms.