KINE 1P90 Lecture Notes - Lecture 3: Endoplasmic Reticulum, Myocyte, T-Tubule

• School: Brock University
• Department: Physical Education and Kinesiology
• Course: KINE 1P90
• Professor: David Ditor

Document Summary

Blue sarcoplasmic reticulum (where calcium is stored) Red rods myofibrils (composed of thick and thin filaments) top myosin molecule each one of the head has two sites. 1) actin binding sites (reaches out grabbing thin filaments. Makes contact on the actin binding site (green circle) 2) myosin atpase site where the enzyme lives (yellow) **atpase is an enzyme that takes the cuts the last phosphate to produce energy** It covers up the binding site so nothing can grab actin (at rest) Troponin binds to tropomyosin, calcium binds to troponin and moves tropomyosin out the way. The sacromere is the functional unit of a muslce fibre purple- thick filaments. Sarcomere = 2 anchors the thin filaments are attached to. Each muscle fibre is made up of smaller fibres called myofibrils. These contain even smaller structures called actin and myosin filaments. These filaments slide in and out between each other to form a muscle contraction.