Muscle Physiology Dynamics of Muscle Contraction MMHS Anatomy.

Slides:

Advertisements

Similar presentations

Advertisements

Muscle Contraction.

Skeletal Muscle Activity: Contraction

Neuromuscular Junction

Muscle Function.

Muscles and Muscle Tissue

CONTRACTION OF SKELETLAL MUSCLE: SLIDING FILAMENT THEORY

Muscular system SKELETAL MUSCLE Skeletal muscle is made up of hundreds of muscle fibers –Fibers consists of threadlike myofibrils –Myofibrils composed.

Anatomy and Physiology I

Sliding Filament Theory Review

Sliding Filament Mechanism

Muscle Physiology Human Anatomy and Physiology.  Beneath the sarcolemma of a muscle fiber lies the sarcoplasmic reticulum (endoplasmic reticulum), which.

How does a muscle work? Remember, muscles can only contract so they can only pull, not push. And it needs certain parts to do this.

Physiology of Skeletal Muscle Contraction. The Muscle Action Potential ( AP ) The Muscle Action Potential ( AP ) Muscle RMP = -90 mV ( same as in nerves.

Histology of Muscle.

Muscle Structure and Function

Contraction of skeletal muscle. Learning objectives What evidence supports the sliding filament mechanism of muscle contraction? How does the sliding.

Myosin Myosin is a protein molecule found in the thick filaments. Myosin is a protein molecule found in the thick filaments.

Muscle Physiology.

BY: STEPHANIE MARTELLA THE CHEMISTRY OF A MUSCLE CONTRACTION.

The Muscular System What do skeletal muscles do? How do muscles work?

Skeletal Muscle Key words:. Overview of the Muscle Fiber Structure Muscle fibers (cells) are composed of myofibrils Myofibrils are composed of myofilaments.

Muscle Contraction Tendon – cord of dense fibrous tissue attaching the muscle to a bone. Epimysium – the sheath of fibrous connective tissues surrounding.

MUSCLE CONTRACTION. Microscopic Anatomy of Skeletal Muscle Sarcomere Contractile unit of a muscle fiber Figure 6.3b.

Muscle Contraction. Muscle Movement Muscle fiber must be stimulated: – By an electrical signal called muscle action potential (AP) – Delivered by motor.

Muscle Cells & Muscle Fiber Contractions

Muscle Physiology Chapter 7.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Muscle Contraction.

Muscles. Muscles work by contracting. Muscles pull. A pair is needed to move a bone two ways. An antagonistic pair.

1 Structure of Skeletal Muscle We will begin our look at the structure of muscle starting with the largest structures and working our way down to the smallest.

Everything you didn’t know you wanted to know.. Microscopic Anatomy of Skeletal Muscle Sarcolema: Plalsma membrane of cell (fiber) Myofibril: Organelle.

Ch : Contraction and Metabolism of Skeletal Muscle

Interaction of thick & thin filaments __________________ –_____________________________________ _____________________________________ –_____________________________________.

Sliding Filament.

Filaments Resting state Electrical impulse (Action Potential) reaches axon terminal.

Synapse – The site of connection between a neuron and a cell. Neurotransmitter – A chemical released at the neuron’s synapse that communicates with the.

The Sliding Filament Theory

Skeletal Muscle Contraction

The Physiology of Skeletal Muscle Contraction

Figure 10.6 Levels of Functional Organization in Skeletal Muscle Fiber

Neuromuscular Junction and Major Events of Muscle Contraction Quiz Review.

Muscular System The 3 Types of Muscles SKELETAL MUSCLE STRUCTURE.

Muscle Contraction. 1.Acetylcholine (Ach) is released from the axon terminal (nerve) into the synaptic cleft and binds to Ach receptors in the sarcolemma.

Sarcomere Physiology: Sliding Filament Theory This is pretty exciting!

Neuron Function The Membrane Potential – Resting potential Excess negative charge inside the neuron Created and maintained by Na-K ion pump Copyright ©

The Muscular System What do skeletal muscles do? How do muscles work?

How do muscle cells contract ?. What is the structure of a muscle fiber ? The sarcolemma, or plasma membrane contains invaginations called T (transverse)

Skeletal Muscle Blank.

The Muscular System What do skeletal muscles do? How do muscles work?

Muscle contraction.

2. Striation Pattern of Sarcomere

Initially Sarcolemma is in the Resting Membrane state

9 Muscles and Muscle Tissue: Part B-Muscle Contraction and Signal Transmission.

The Muscular System What do skeletal muscles do? How do muscles work?

Muscle Contraction.

Introductory Skeletal Muscle – Histology Flash Cards

Physiology of Muscle Contraction

Neuromuscular Function

Prayer Homework Attendance.

NOTES: The Muscular System (Ch 8, part 2)

Biology 211 Anatomy & Physiology I

The Muscular System.

Gnarly Nervous Physiology

MUSLCES PART 2 HOW DO THEY WORK?.

Physiology of Muscle Contraction

Sliding Filament Theory

Contraction of Skeletal Muscle

Presentation transcript:

Muscle Physiology Dynamics of Muscle Contraction MMHS Anatomy

Thick and Thin Filaments A. Muscle movement (=contraction) occurs at the microscopic level of the sarcomere. B. Sliding Filament Mechanism 1. Actin (thin) myofilament slides along the myosin (thick) myofilament. 2. Z lines that form the boundary of the sarcomere move toward each other along the length of the muscle. =this causes the muscle to shorten (=contractibility).

The Neuromuscular Junction

Muscle Cell Parts 1.Sarcolemma = the muscle membrane 2.Sarcoplasm = the muscle cytoplasm 3.Sarcoplasmic reticulum 3.Sarcoplasmic reticulum = organelle responsible for protein production.  This contains high amounts of Ca +2 ions.

Sarcomere Parts 1.Z lines: boundary of the sarcomere. 2.I Band: region of only actin myofilaments. 3.H Zone: region of only myosin myofilaments. 4.A Band: region of both actin and myosin. 5.M-Line: The exact midpoint of the sarcomere.

The Sarcomere

Muscle Contraction—10 Steps 1.A nerve impulse enters the presynaptic terminal (nerve) of the neuromuscular junction. 2.The impulse causes Ach to be released from the synaptic vessicles in the axon terminal. 3.Ach diffuses across the synaptic cleft and opens Na+ channels in muscle membranes. 4.Na+ enters the muscle cell and depolarizes it. 5.“T” tubules carry impulses into the sarcoplasmic reticulum and releases Ca 2+ ions.

10 steps of Muscle Contraction 6.Ca +2 enters the individual muscle fibrils and binds to troponin molecules on tropomyosin strands moving the strand and exposing the binding sites. 7.Myosin binds to actin forming crossbridges that ATP can bind to. 8.ATP breaks down, releasing energy, causing cross bridges to pull actin strand.

10 steps of muscle contraction 9.Another ATP binds to myosin cross bridge for the recovery stroke. (bend, attach, and pull) on the actin strand. 10.When the action potential ends Ca +2 ions are pumped back into the sarco. retic. Tropomyosin covers the binding sites and myosin can no longer bind.

The thin filament showing what happens when Calcium binds. 1.Calcium binds to the troponin complex. 2. Tropomyosin moves exposing the binding sites. 3. Now exposed so the heads of the thick myosin filament can bind to the actin.

The Myosin Cross-Bridge Formation Read the step- wise captions explaining how the cross- bridge process works. Identify: 1.Working stroke 2.Recovery stroke 3.Cross Bridge. 4.ATP + ADP