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.
There are two basic types of T lymphocytes: T-helper cells (CD4+ cells) and T-cytotoxic cells (CD8+ cells). When activated, the T-cytotoxic cells can eliminate the host cells that are infected with virus, Mycobacteria, certain intracellular bacteria, fungi, parasites, and tumor cells.