HSCI 100 Lecture Notes - Lecture 9: Endoplasmic Reticulum, Action Potential, Myofibril

• School: Simon Fraser University
• Department: Health Sciences
• Course: HSCI 100
• Professor: Nienke Van Houten

Document Summary

Involved with movement that allows us to respond to stimuli, digest food, return blood to heart, respiration. Bones store & release calcium need for muscle contraction, blood clotting, nerve impulse conduction. Attachments: tendon connective tissue that connects muscle to bone. Origin attachment of muscle on a stationary bone. Insertion attachment of a muscle on a bone that moves. Action: antagonistic muscles that work in opposite pairs, synergistic muscles working in groups for a common action. Muscle ibers are arranged in bundles called fascicles. Myoibrils are bundle of myoilaments that run the length of a iber. Myoilaments are 2 main proteins (actin & myosin) that are arranged in repeating units. Sarcomeres- repeating units of actin & myosin found along a myoibril. Mature muscles have satellite cells serve as stem cells for this tissue. Sarcoplasmic reticulum- stores ca+ ions; releases them when muscle cell is stimulated. Myosin thick ilaments; motor protein uses atp to create movement.