Skeletal & Muscular Systems
Grade 12
Alyson Slomko
Skeletal System
 Provides the basic
framework for the body
 Plays a crucial role in
movement
 Protects internal organs
and tissues from trauma
Structure of the Skeletal System
 206 Bones
 Bones store calcium and phosphorus
 Bone Marrow produces new red and white blood cells
and platelets
 Consists of Axial Skeleton and Appendicular Skeleton
More Basic Information About
Skeletal System
Axial & Appendicular Skeletons
 Axial Skeleton:
 Consists of 80 bones
 Includes the skull, spine, ribs, vertebrae and sternum
 Appendicular Skeleton:
 Composed of the remaining 126 bones of the upper and
lower limbs, shoulders and hips
Types of Bones
Irregular Bones
Long Bones
Ossification
Cartilage
Short
Bones
Flat Bones
Long Bones
 Bones of legs and arms
 Diaphysis: main column of
the long bone that contains
yellow bone marrow (fats)
 Epiphysis: end of the long
bone that forms joints and
contains red marrow (blood
cells)
Short, Flat & Irregular Bones
 Short Bones: bones that are
almost equal in length and
width
 Wrists and ankles
 Flat Bones: thinner and flatter
bones
 Ribs, skull, shoulder blade
 Irregular Bones: irregularly
shaped
 Facial bones and vertebrae
Cartilage & Ossification
 Cartilage: strong, flexible
connective tissue
 Found at the end of the long
bones, nose and outer ear
 Acts as cushion, reduces
friction and allows smooth
motion
 Ossification: process by
which bone in formed,
renewed and repaired
Joints
Ball-and-Socket
Hinge
Pivot
Gliding Joints
Tendon
Ligament
Ball-and-Socket Joint
 Formed when rebound head fits into rounder cavity
of joining bone
 Provides the widest range of motion in all directions
Examples: hip and shoulder
Hinge & Pivot
 Hinge: allows for bending and straightening and
promotes rotation
 Elbow, knee, ankle and fingers
 Pivot: limited rotation
 Neck and head
Gliding Joints
 An oval shaped part that fits into a curved space
 Allow bones to slide over one another
Example: wrist
Ligaments & Tendons
 Ligament: bands of fibrous,
slightly elastic connective
tissue that attaches bone to
bone and stabilize
movement at joint
 Tendons: fibrous cord that
attaches muscle to bone
Muscular System
 Connected to Bone by tendons
 Performs work in the body
 Voluntary: allows you to make movement when you
want or need to
 Involuntary: process that happens without conscious
control
Types of Muscle
Smooth Muscle
 Acts on the lining of passageways and internal organs
 Involuntary
 Examples: blood vessels, digestive tract, lungs,
bladder
Skeletal Muscle
 Attached to the bone and causes body movements
 Voluntary
 Flexor: muscle that closes a joint
 Extensor: muscle that opens a joint
Cardiac Muscle
 Type of striated muscle that forms the walls of the
heart
 Involuntary
 The heart contracts about 100,000 times a day
Major Muscle Groups (Skeletal)
Abdomen
Back
Shoulders
Legs
Arms
Chest
Problems Associated with the
Muscular System
 Atrophy: decrease in size and strength
 Overuse: strain (tendon), sprain (ligament), tear,
soreness, cramps
 Tendonitis: inflammation of a tendon
 Hernia: when organ tissue protrudes through an area
of weak muscle
 Muscular Dystrophy: inherited disorder in-which
skeletal muscle are progressively destroyed
Needs of the Muscular System
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Weight bearing activity
Flexibility
Proper warm-up
Protein
RICE (rest, ice,
compression, elevation)