Skeletal/Muscle Systems

Skeletal System

Skeletal Muscles

Joints

Major Functions

Structure

Compact vs Spongy Bone

Long Bone

Bone Marrow

Bone Cells

Fibrous

Synovial

Cartilagenous

Types of Synovial Joints

Plane

Hinge

Pivot

Condylar

Saddle

Ball-and-socket

Functions

Properties

Muscle Fibers

Neuromuscular Junction

Support

Assist w/ Movement

Protection

Mineral Storage

Blood Cell Formation

Energy Storage

Framework for Soft Tissue connection

Tendons (Muscle--Bone)

Ligaments (Bone--Bone)

Eg. Cranium, Vertebrae, Thoracic (Rib) Cage

Calcium + Phosphorous

Body may go to these deposits to restore normal levels in the blood

Happens in Red Bone Marrow

Nutrients from Fat

"Yellow" Bone Marrow

Bone

Tendons/Ligaments

Articulation

Cartilage

"All Together"

Joints

Organic Portion (35%)

Inorganic Portion (65%)

Cells

E.C. Matrix

Collagen Fiber

Minerals (for Hardness)

Calcium

Phosphorous

Made of Dense Regular C.T.

Hyaline

Fibro-

Costal (Rib)

Nasal

Articular

Found in Articulated Joints (At end of Bones in joint)

Intervertebral Discs

Pubic Symphysis

Menisci of Knees

Components

Compact Bone

Spongy Bone

Periosteum

Covers Bone, made of Dense Irregular C.T.

Perforating Canal

Osteons

Lamellae

Location

Structure

Ends of Long Bone

Fills Space b/t compact bone in Flat Bones

Red Bone Marrow

NO Osteons

Tebeculae

Endosteum

Osteogenic

Structure

Compact

Spongy

Cartilage

Epiphyses (Ends)

Diaphysis (Middle)

Epiphyseal Line (Plate when growing)

Hyaline Cartilage; Ossifies through growth

Compact Bone

Articular Cartilage

Membranes

Compact Bone

Periosteum (Outside)

Spongy Bone

Medullary Cavity

Endosteum (Inside)

Outside Layer

Inside (Cellular) Layer

Dense Irregular C.T.

Osteogenic; Place of Attachment for Ligaments/Tendons

Location

Types

Red

Yellow

Red

Yellow

Found in ALL Bone from Fetus-7 Years

When Adult: Found in Axial Skeleton

All Spongy Bone

All other bones outside of Axial Skeleton after 7 Years Old

Composition

Function

Compostion

Function

Nutrient Storage

Adipose Tissue

Gelatinous, Soft Tissue

Blood Cell Formation

Stem Cells

Osteoblast

Located in Peri- and Endosteum

Osteocyte (in Lacuna)

More Stem Cells

Function: Create E.C. Matrix

Osteoclasts

Located in ANY Bone Tissue

Maintain healthy bone tissue

Fusion of Several Leukocytes

Multinucleate

VERY Large

Mobile

Phagocyte (for Oragnic material)

Has Microvilli

Secretes Enzymes that break down Bone

Inorganic material (minerals) absorbed into Blood

Organic material broken down by cell

Synchondroses

Symphyses

Found in Sutures of Cranial bones

Tight, Rigid, Immovable

Structure

Location

Made of Hyaline Cartilage

Found in Epiphyseal Plate + B/t First Rib and Manubrium

Made of Hyaline Cartilage (lateral) and Fibrocartilage (medial)

Found in Pubic Symphysis + Intervertebral Joints

Immovable

Slightly Moveable (Giving Birth, Bending Spine)

Joint Capsule

Joint Cavity

Synovial Membrane + Fluid

Outer Layer

Inner Layer

Dense Regular C.T. (Continuous w/ Periosteum)

Areolar C.T. (Synovial Membrane)

Filled w/ Synovial Fluid (made by Synovial Membrane)

Fluid: Reduces Shock, Nourishes Articular Cartilage

Where Two Long Bones meet (Types BELOW)

Found w/ Flat, articulated surfaces (Intercarpal/intertarsal)

Nonaxial, Gliding Movement

Trough of one bone moves around cylinder of another

Uniaxial Movemnet, Flexion + Extension Movements (Elbow)

Axle Bone moves in Sleeve (created by bone and surrounding ligament)

Uniaxial Movement; Roation (eg. Radius around Ulna)

Convex Oval inside Concave Oval (Articulated Surfaces)

Biaxial Movement

Medial/Lateral Axis

Anterior/Posterior Axis

Flexion/Extension

Adduction/Abduction

Bone sits in a "saddle" of another bone

Biaxial Movement

Adduction/Abduction

Flexion/Extension

Articular Surfaces are both concave and convex

Spherical Head (Ball) of one bone sits in Cup (Socket) of another bone (eg. Shoulder/Hip)

MultiAxial movement

Flexion/Extension (along Medial/Lateral Axis)

Adduction/Abduction (along anterior/posterior axis)

Rotation (around Vertical Axis)

Produce Movement

Open/Close Body passageways

Maintain Posture

Generate Heat

Contractility

Excitability

Extensibility

Elasticity

Sphincter Muscles

Anus

Urethra

Iris

Pyloric Valve

Stabilize Joints

Shivering

Create Force/Tension while pulling on attachment point (on bone)

Actin + Myosin=Contraction

Respond to stimuli

Produce Electrical signal

Ability to stretch (to a limit)

Ability to return to original shape (after contraction/extension)

Organization (Connective Tissue + Muscle Levels)

Muscle Organ

Made up of Groups of Fascicles

Surrounded by Epimysium (Dense Irregular C.T.)

Made up of Groups of Muscle Fibers

Surrounded by Perimysium (Dense Irregular C.T.)

Surrounded by Endomysium (mostly Reticular Fibers)

Sarcolemma

Transverse (T) Tubules

Sarcoplasmic Reticulum

Myofibrils

Mitochondria

Microscopic Components

Site of ATP Synthesis (ATP used in Muscle Contraction)

Web-like structure over individual fibril; Includes Terminal Cistern (storage for Calcium)

Cell membrane over Muscle Fiber; Invaginates through T Tubules

Invagination through muscle fibers; continuation of Sarcolemma

Made up of Myofibrils

Surrounded by Sarcolemma

Sarcomere

Z-Disc

Myosin

Actin

A-Band

I-Band

M-Line

Basic unit of contraction; Z-Line-Z-line along myofibril

Zig-Zag line that Actin attaches to

"Thick Filament"

"Thin Filament"

"Dark Zone" One end of Myosin-to the other (across the M-Line)

"Light Zone" End of Myosin- another (over the Z-Disc)

3-pronged line through middle of A-Band; Site of attachment for Myosin