Main article: Nicotinic acetylcholine receptors. The nAChRs are ligand-gated ion channels, and, like other members of the cys-loop ligand-gated ion channel superfamily, are composed of five protein subunits symmetrically arranged like staves around a barrel.
Acrylonitrile butadiene styrene, otherwise known as ABS plastic, is a lightweight material popularly used in children's toys. There are two types: one suited for extrusion molding and one for injection molding. LEGO blocks are made from ABS plastic because it is so light and durable. Continue Reading.
1 Durable poly in assorted colors (blueberry, lime, grape) is wear, tear and mositure-resistant. 2  Snap closure keeps contents secure and open pocket on back keeps additional contents at hand.  Letter size.