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Recycling of Acetylcholine


One of the main functions of acetylcholine is to carry signals from neurons to muscles. Once the synaptic transmission is done, acetylcholine in the synapse will be degraded immediately. Catalyzed by the enzyme cholinesterase, acetylcholine is turned into acetic acid and choline. The choline part then gets transported back to the presynaptic terminal via the ${Na}^{-}$ co-transporter. There, choline is synthesized into acetylcholine and starts the cycle again.

Which of the following is INCORRECT about this process?


The recycling process of acetylcholine prevents the neurotransmitter from being effective for a long time.


Cholinesterase is one of the enzymes that has low catalytic efficiency.


Choline can be reused once it is back in the cell.


Organophosphorus compounds interrupt the synaptic transmission by binding to cholinesterase.