Musculoskeletal system

Concepts to MasterBones – Joints - Muscles

Bones

Head Trunk Limbs

Fact: 206 Bones divided into 3 regions.

Definition: A Bone is a hard solid organ that forms part of the skeleton.

Types of Bone: spongy and compact

BonesCategories of Bones

Long Bones: longer than wide-thin body (diaphysis) rounded ends (epiphysis)

Short Bones: cubic in shape, mostly spongy bone – wrists and ankles

Flat Bones: Thin flat and curved – a sandwich of spongy and compact bone. – skull, ribs scapula

Irregular Bones: not covered by the other categories because of their irregular shape – spine

Bones

Femur Wrist Hip Scapula

BonesFunction of Bones

Support: Keeps us vertical: supports soft organs (heart, lungs, liver, intestines)

Protection: Organ protection – brain, heart, lungs

Movement: bones act as levers during muscle movement.

Storage: fat storage – mineral storage – calcium, phosphorus

Production of Blood Cells: in the bone marrow – red blood cells, white blood cells, platelets.

JointsA junction between two or more bones Mobility of Joints

Fixed: skull, hip

Semi movable: vertebrae

Freely Movable: shoulder

Mechanics of a Joint

Extension/Flexion

Abduction / Adduction

Rotation

Muscles

Muscles have the ability to contract causing our bodies OR our internal organs to move.

Muscle Functions:• Movement• Posture Maintenance• Joint Stabilization• Heat Release

Muscles

Three distinct types of muscles carry out the functions described on the previous slide.

Muscle Types:• Smooth Muscles• Cardiac Muscle• Skeletal Muscle

Muscle Properties:Skeletal Muscles: • Voluntary muscles that are attached to the skeleton. • Can react with great force for short periods of time.• Composed of bundled muscle fibers.• Muscle is fibers and bundles are covered with connective tissue.• Connective tissue fuses at the ends of muscles for form tendons.• Tendons attach bone to muscle.

Smooth Muscles: • Involuntary muscles that make up the wall of internal organs. • The help move substances from place to place.• Work slower than skeletal and tire less easily.

Cardiac Muscle: • A unique muscle that makes up the heart.• Involuntary muscle like smooth muscle.• Structure similar to skeletal muscle.• Great strength and endurance.• Contraction causes blood to flow throughout the body.