Chapter 9: Muscular System

Lecture #1

What is Moebius syndrome?

• Absence of the sixth and seventh cranial nerves which carry impulses from the brain to the muscles of the face

• Symptoms?

What treatment did Chelsey Thomas receive?

• Underwent two ‘smile’ surgeries

• At 7yo, transplant of nerve and muscle tissue from legs to either side of her mouth

3 Types of Muscle Tissue

• Skeletal Muscle Tissue

• Cardiac Muscle Tissue

• Smooth Muscle Tissue

Skeletal Muscle Tissue

• Tissues you’ll find in skeletal muscle

Ske le tal Musc le Tis sue

Nervous Tis sueBlood

Conne ctive Tis sue

Structure of a Skeletal Muscle

A. Connective Tissue Coverings

:Fasc ia

- s e parate s individualmusc le

- holds musc le in pos ition

- . .dense c t

- proje c ts be yond musc le to form tendon

Structure of a Skeletal Muscle

A. Connective Tissue Coverings

:Tendon

- may inte rtw ine w ithpe rios te um

Structure of a Skeletal Muscle

A. Connective Tissue CoveringsTendons :

musc le to boneattachment

Aponeurose s : fibrous she e ts

attaching to bone or to othe r musc le

Tendinitis & Tenosynovitis

• Green box on p. 286

• What is it & what causes it?

• Where is it most commonly found?

Structure of a Skeletal Muscle

• Epimysium

• Perimysium

• Endomysium

muscle

fascicle

Musclefiber

Myofibril

C.T. Functions

• E• P• E

• Functions: allows parts to move somewhat independently

• Also, blood vessels and nerves pass through these layers

Compartmentment Syndrome

• Green box on p. 286• What is it?

• What is the treatment?

Fascia layers (c.t. layers)

• Fascia is interconnected throughout body to• Deep fascia: surrounds muscle• Subcutaneous fascia: just beneath the skin• Subserous fascia: c.t. layer of serous

memb over organs and in body cavities

Structure of a Skeletal Muscle• C.T. coverings

• Skeletal Muscle Fibers

2. Aponeurosis &Tendons

1. Fascia 3. EpimysiumPerimysiumEndomysium 4. fascicles

Structure of a Skeletal Muscle• Skeletal Muscle Fibers

Structure of a Skeletal Muscle• Skeletal Muscle Fibers

Structure of a Skeletal Muscle• A Single Muscle Cell = Muscle ________

• Forms from many undifferentiated cells that fuse during development

• CHARACTERISTICS:• MULTINUCLEATED• THIN• ELONGATED CYLINDER WITH ROUNDED

ENDS

Structure of a Skeletal Muscle

• Sarcomeres connected end-to-end make up ______________

• Functional unit of muscle contraction = _______________

• Striation pattern