(a(i))[4]
State the exact location in a cholinergic synapse that fits each description. A region packed with many mitochondria. A region where ACh is released by exocytosis. A region containing voltage-gated channel proteins. A region containing ligand-gated channel proteins.
(a(ii))[2]
Outline the roles of synapses in the nervous system.
(b)[4]
Some insecticides contain compounds known as organophosphates. Organophosphates may act as enzyme inhibitors in neuromuscular junctions. People who use organophosphates and do not follow safety guidelines risk organophosphate poisoning, which impairs muscle function. Suggest how organophosphates could affect muscle function in humans.
(c)[2]
Outline the role of the sarcoplasmic reticulum during the contraction of striated muscle.