A cataract is a clouding of the lens in the eye that affects vision. Most cataracts are related to aging. Cataracts are very common in older people. By age 80, more than half of all Americans either have a cataract or have had cataract surgery.
Acetylcholine. Acetylcholine (ACh) is the transmitter released by the preganglionic nerve terminals of both the sympathetic and the parasympathetic divisions (Fig 6.2). The synapse at those sites utilizes a nicotinic receptor similar in structure to the receptor at the neuromuscular junction.
acetylcholine is released from the end of the motor neuron. The first event in muscle fiber contraction is that. -the muscle fiber membrane is stimulated and a muscle impulse travels deep into the fiber through transverse tubules. -acetylcholine diffuses across a gap at a neuromuscular junction. -acetylcholine is released from the end of the motor neuron.