Boundless Essay

592 WordsNov 18, 20143 Pages
Boundless, 2011. Excitation–contraction coupling is the connection between the electrical action potential and the mechanical muscle contraction. [Online] Available at: <https://www.boundless.com/biology/the-musculoskeletal-system/muscle-contraction-and-locomotion/excitation-contraction-coupling/> [Accessed on 1 May 2014] Chalovich. J M, (no date0. Muscle contraction. An overview. Brody School of Medicine at East Carolina University [Online] Availab;e at: http: <www.biophysics.org/Portals/1/PDFs/Summer%20Course/11_Lecture%2021%20chalovich%20muscle.pdf> [Accessed on 1 May 2014] Contraction occurs by sliding of actin and myosin filaments in ATP dependent process. When the thick filaments known as myosin slide past the thin filaments known as actin this is when shortening of the muscle occurs (Chalovich, no date) Key Points * A motor neuron connects to a muscle at the neuromuscular junction, where a synaptic terminal forms a synaptic cleft with a motor-end plate. * The neurotransmitter acetylcholine diffuses across the synaptic cleft, causing the depolarization of the sarcolemma. * The depolarization of the sarcolemma stimulates the sarcoplasmic reticulum to release Ca2+, which causes the muscle to contract. Terms motor-end plate post junctional folds which increase the surface area of the membrane (and acetylcholine receptors) exposed to the synaptic cleft sarcolemma a thin cell membrane that surrounds a striated muscle fibre acetylcholinesterase an enzyme that catalyzes the hydrolysis of the neurotransmitter acetylcholine into choline and acetic acid Examples * Critique- Without the breakdown of acetycholine, motor neurons fire continuously. Sarin is extremely fatal and causes nausea and drooling followed by the loss of all bodily functions. A lethal exposure to Sarin can cause death within one minute. A neural signal is the

More about Boundless Essay

Open Document