In humans, the products of anaerobic respiration are adenosine triphosphate (ATP), carbon dioxide and lactic acid. ATP is the molecule that provides energy to cells.
Two Types of Receptors. There are two types of acetylcholine receptors (AChR) that bind acetylcholine and transmit its signal: muscarinic AChRs and nicotinic AChRs, which are named after the agonists muscarine and nicotine, respectively.he muscarinic AChRs occur primarily in the CNS, and are part of a large family of G-protein-coupled receptors (G proteins), which use an intracellular secondary messenger system involving an increase of intracellular calcium to transmit signals inside cells.
1 Once inside a target cell, the hormone (pink) binds to a receptor (purple) - similar to a hand sliding in a glove or mitten-and forms what is known as a hormone-receptor complex between the ligand and receptor.2  A ligand is any molecule that binds to a specific site on a protein or other molecule. In this case, the estrogen hormone 17-beta-estradiol is the ligand, and the estrogen receptor is the protein. 2  Binding turns on, or activates, a hormone receptor. 3  Activation sets in motion cell signaling systems that trigger gene expression and lead to responses typical of a particular hormone.