muscles - b. Myosin heads = cross bridges - attach, detach,...

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
1. 1Part 1 - Muscle contraction a. Neuromuscular junction i. Nerve cell ----> muscle fiber (Neuron) (synaptic cleft) (sarcolemma) motorend plate ii. Axonal terminal ----> releases Ach (acetylcholine = neurotransmitter) (Due to action potential) into synaptic cleft iii. Na+ gates open on sarcolemma = upsets membrane balance Electrical current = action potential in muscle fiber iv. Action potential travel to SR —> release of Ca+ 2. Part 2 - sliding filament model a. Ca+ ions bind troponin and tropomyosin, move them “out of the way,” exposes active site on actin molecules
Background image of page 1
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: b. Myosin heads = cross bridges - attach, detach, several times c. Lots of energy needed, ATP 3. Energy sources for muscle contraction a. Creatine phosphate (CP) i. Creation of ATP from ADP very quickly ii. Runs out fast b. Aerobic respiration - needs oxygen i. 1 molecule of glucose > 36 ATPs (slower then CP) c. Anaerobic metabolism - no oxygen required i. Not efficient - 1 glucose - 2 ATPs ii. Causes buildup of lactic acid 4. Motor unit - one nerve cell and all the muscle cells it stimulates...
View Full Document

Ask a homework question - tutors are online