See Also: nicotinic acetylcholine receptor(medicine)
muscarinic acetylcholine receptor(medicine)
acetylcholine receptor antibodies(medicine)
nicotinic cholinergic receptor(medicine)
geologic(dictionary)
geologic time(encyclopedia)
geologic sediments(medicine)
ACh (acetylcholine)(health)
Acetylcholine(medicine)
Acetylcholine(health)

geologic time (sh) and nicotinic acetylcholine receptor (medicine)


geologic time (sh)




Interval of time occupied by the Earth's geologic history, extending from งใ 3.

9 billion years ago (corresponding to the age of the oldest known rocks) to the present day. It is, in effect, the part of the Earth's history that is recorded in rock strata. The geologic time scale is classified in nested intervals distinguished by characteristic geologic and biologic features. From longest to shortest duration, the intervals are eon, era, period, and epoch.


nicotinic acetylcholine receptor (medicine)


nicotinic acetylcholine receptor
Integral membrane protein of the postsynaptic membrane to which acetylcholine binds. The receptor contains an integral ion channel, as a result of binding of acetylcholine, ion channels in the subsynaptic membrane are opened. at the neuromuscular junction, the nicotinic acetylcholine receptor initiates muscle contraction. Currently the best characterised ion channel protein: made of a hetero pentamer of related subunits, although a homo pentamer is functional in insects. Structural studies show that the acetylcholine binding site and the ionic channel are part of the same macromolecular unit. The nAChR mediates rapid transduction events (1ms) whereas receptors activating G-protein coupled channels operate on slower time scales (millisecond to second range).