Physiology 2130 Lecture Notes - Lecture 5: Myosin Head, Troponin, Troponin C

• School: Western University
• Department: Physiology
• Course: Physiology 2130
• Professor: Christine Bell

Document Summary

Physiology 2130 distance studies module 5 muscles. Three types of muscle cells: skeletal muscle used primarily for voluntary motion, smooth muscle found within blood vessel walls, airways, various ducts, urinary bladder, uterus, and digestive tract, cardiac muscle heart. Three principal functions: movement, heat production, body support + posture. This module will focus on skeletal muscle + movement. Each fascicle = groups of muscle cells or fibres. Each muscle cell contains bundles of myofibrils. Each myofibril contains thick and thin myofilaments. Thin filament = mostly actin along with troponin and tropomyosin. Muscle contraction = interaction between thick and thin myofilaments. Perimysium: white connective tissue that surrounds bundles of fasciculi. Sarcolemma: muscle cell membrane over which action potential is transmitted. Transverse (t) tubules: small tube-like projections on sarcolemma that extend into cell: conduct action potential deep into cell where contractile proteins are. Muscle cells are one of few body cells that contain more than one nucleus.