Clostridium botulinum is a bacterium that produces botulinum toxin that inhibits the release of acetylcholine. Which description best fits how muscle cells will respond to a lack of acetylcholine?

muscle cells will become paralyzed when there is a lack of acetylcholine

Explanation:

Based on the information provided within the question it can be said that in this scenario the muscle cells will become paralyzed when there is a lack of acetylcholine. That is because the Acetylcholine (ACh) is an organic chemical within the brain and body that acts as a neurotransmitter to send signals from the brain to the muscle cells. Without those signals the muscle cells cannot respond and are therefore paralyzed.

paralysis of muscles cells will set-in

Explanation:

For skeletal muscles to contract, Neurotransmitter Acetycholine in the synaptic cleft, diffuses across the synapse to bind with the membrane receptors (sacolemma) of the post-synaptic muscle fibre.

This acetrycholine-recepetor binding stimulated opening of Ligand-gated Sodium channels, leading to depolarization. If the stimulus is upto threshold levels, Action potential is generated, and propagated along sacolemma reticulum to the centre of muscle fibre.

The arrival of action potential stimulated the the opening of Voltage gated Calcium Channels, and Ca + diffuses out of the Sacoplasmic reticulum.

This is followed by the binding of Ca + to troponin, which prompted tropomyosin exposure of myosin-binding site, and the consequent formation of cross-bridges. The sacolemma is then shortened, and the muscle contracts.

Now if the receptor - binding action of acetycholine is inhibited by botulinum, the excitatory action of acetycholine will seize. Depolarization will not occur, the muscle cells will be in permanent state of membrane potentials, action potential will not be generated and the muscles will be paralysed.