Question

Lack of acetylcholine results in easy fatigue and muscle weakness, especially in muscles engaging in repetitive action. Weakness of respiratory muscles can lead to respiratory arrest if untreated. What is the function of acetylcholine in maintaining respiratory function?

1) Acetylcholine helps in the contraction of respiratory muscles.
2) Acetylcholine helps in the relaxation of respiratory muscles.
3) Acetylcholine helps in the transmission of nerve signals to respiratory muscles.
4) Acetylcholine helps in the production of oxygen in the respiratory system.

Answer 1

Acetylcholine (ACh) is critical for the contraction of respiratory muscles as it transmits signals from motor neurons to muscles. A lack of acetylcholine can lead to muscle weakness and potentially respiratory arrest.

Step-by-step explanation:

The function of acetylcholine (ACh) in maintaining respiratory function is primarily related to its role as a neurotransmitter, which is crucial for muscle contraction, including the contraction of respiratory muscles. Acetylcholine helps transmit signals from motor neurons to respiratory muscles, allowing for the rhythmic contractions necessary for breathing. When acetylcholine binds at a motor end-plate, it triggers depolarization and an action potential that results in muscle contraction. Without adequate acetylcholine, these contractions would be impaired, leading to muscle weakness and potential respiratory failure. Conditions like myasthenia gravis, where acetylcholine receptors are impaired, or exposure to substances like botulinum toxin, which prevents acetylcholine release, can lead to serious complications including respiratory arrest.