Вопрос
Which of following statements is not correct? An acetylcholine release at a neuromuscular junction Bbl6epure oAMH OTBeT: a. both Cand D are true b. always causes a muscle fiber-to contract c. is followed by rapid destruction of acetylcholine d. increases sodium movement into a muscle cell e. produces an end-plate -potential
Решения
4
(250 Голоса)
Ираклий
элита · Репетитор 8 лет
Ответ
The correct answer is c. is followed by rapid destruction of acetylcholine.Explanation:a. both Cand D are true - This statement is not correct because statement c is not true.b. always causes a muscle fiber-to contract - This statement is correct. The release of acetylcholine at a neuromuscular junction always causes a muscle fiber to contract.c. is followed by rapid destruction of acetylcholine - This statement is not correct. Acetylcholine is rapidly broken down by the enzyme acetylcholinesterase in the synaptic cleft, but it is not immediately destroyed.d. increases sodium movement into a muscle cell - This statement is correct. The binding of acetylcholine to its receptor on the muscle cell membrane (sarcolemma) causes sodium ions to enter the muscle cell, leading to depolarization and muscle contraction.e. produces an end-plate potential - This statement is correct. The binding of acetylcholine to its receptor on the muscle cell membrane (sarcolemma) produces an end-plate potential, which is the initial depolarization of the muscle cell membrane.