Question

Resting potential has been drawn for you. Continue that line to show what would happen to membrane potential in the POSTsynaptic muscle cell if the person was exposed to cyclosarin. Cyclosarin prevents acetylcholinesterase (the enzyme that breaks down the neurotransmitter) from breaking down acetylcholine (the neurotransmitter). Membrane Potential * Clear sketch Submit response I Switch to text response

Answer 1

sarin is a potent inhibitor of acetylcholinesterase, an enzyme that degrades the neurotransmitter acetylcholine after it is released into the synaptic cleft. In vertebrates, acetylcholine is the neurotransmitter used at the neuromuscular junction, where signals are transmitted between neurons from the central nervous system to muscle fibres. Normally, acetylcholine is released from the neuron to stimulate the muscle, after which it is degraded by acetylcholinesterase, allowing the muscle to relax. A build-up of acetylcholine in the synaptic cleft, due to the inhibition of acetylcholinesterase, means the neurotransmitter continues to act on the muscle fibre, so that any nerve impulses are effectively continually transmitted.

Sarin acts on acetylcholinesterase by forming a covalent bond with the particular serine residue at the active site.