Cattle : âBeefâ cattle slaughtered at 18 months young; dairy cows slaughtered at 4 to 5 years young; Natural life span: 18 to 25+ years. Veal Calves: Slaughtered at 16 weeks young; Natural life span: 18 to 25+ years. Goats: Slaughtered at 3 to 5 months young; Natural life span: 12 to 14 years.
Definition of Ion channel. Ion channel: A protein that acts as a pore in a cell membrane and permits the selective passage of ions (such as potassium ions, sodium ions, and calcium ions), by means of which electrical current passes in and out of the cell.
The three main groups of ion channels are 1) the voltage-gated channels such as the sodium and potassium channels of the nerve axons and nerve terminals, 2) the extracellular ligand-activated channels which includes channels such as GABA and glycine receptor channels, most of which are regulated by ligands that are neurotransmitters.