Download Types of Bones

Skeletal System
Functions of the Skeletal System:
 Allows movement
 Protects organs
 Bones are the principal storage place for essential body
minerals
o Calcium
o Phosphorus
 Production of red and white blood cells in the red marrow
of the bone.
Structure of the Skeleton:
Divided into two main parts:
Axial skeleton: (Green)
 Includes the bones of the skull, the
sternum, the ribs, and the vertebrae
Appendicular skeleton: (Purple)
 Includes the 126 bones of the shoulders
arms, hands, hips, legs, and feet.
Types of Bones:
Long Bones: Examples of long bones include the bones in
your legs, arms, fingers and toes.
 Diaphysis: Main column of long bones.
o Within the diaphysis is a narrow
cavity that contains yellow bone
marrow
o Yellow bone marrow stores fat.
o If necessary, the Yellow bone
marrow will convert in to red blood
marrow.
 Epiphysis: The end of the long bones.
o Forms joints with other bones
o Contains red bone marrow
Short Bones: Are almost equal in length and width.
Flat Bones: Are somewhat thinner and much flatter than
other bones.
 Flat bones protect internal organs
 Contains red bone marrow
Irregular Bones: Are bones that have unusual shapes and
do not fit into the other categories.
Cartilage:
 Strong, flexible material that provides a smooth surface at
a joint.
 Supports the nose and ears
 Connects the ribs to the sternum
 Acts as a cushion between adjoining vertebrae
Ossifications: Is the process by which bone is formed,
renewed, and repaired
 As the body grows, bone cells and minerals replace the
cartilage cells.
Joints: The point at which two bones meet and allow
movement of the body framework
Type of Joints:
Ball-and-socket joints: Formed when the rounded head of
one bone fits into the rounded cavity of an adjoining bone.
 These joints allow the widest range of movement in all
directions
 Examples: Hips and Shoulders
Hinge Joints: Allows a joint to bend and straighten,
promoting rotation.
 Examples: Elbows, knee, ankle, and fingers
Pivot: Allow limited rotation or turning of the head.
Ellipsoidal Joints: Gliding joints that allow bones to slide
over one another.
 Example: Wrists
Ligament: Band of fibrous, slightly elastic connective
tissue that attaches bone to bone
 Help stabilize the movements of bones at a joint
 Holds bones in place
Tendon: Fibrous cord that attaches muscle to the bone
PROBLEMS OF THE SKELETAL SYSTEM:
Bone fractures: Break in the bone
 Hairline fracture: Incomplete and the two parts of the
bone do not separate.
 Transverse Fracture: Fracture is completely across the
bone.
 Comminuted Fracture: The bone shatters into more than
two pieces, usually as a result of severe force.
Scoliosis: is lateral, or side-to-side, curvature of
the spine
Osteoporosis: Condition that results from a loss of calcium
in the bone and becomes brittle.
Injury to the joints:
 Sprains: occurs when tissue around the joint is twisted or
receives too much pressure. (Damage to Ligaments)
 Dislocation: Results when a bone slips from its normal
position at a joint.
 Torn cartilage: It results from a sharp blow or severe
twisting of a joint.
 Bunion: Painful swelling of the bursa in the
first joint of the big toe.
 Bursitis: Inflammation of a fluid-filled sac
called the bursa.
 Arthritis: inflammation of the joints.
Repetitive Motion Injury: Damage to tissues caused by
prolonged, repeated movements.
The Muscular System
Muscles in your body are responsible for moving bones,
pumping blood, moving food through the digestive system,
and controlling air movement in and out of the lungs.
Involuntary Movement: A process that happens without
your conscious control.
Voluntary Movement: A process that happens with your
conscious control.
Structure of the Muscular System:
 A muscle consists of mass of fibers grouped together.
 Almost all individual muscles fibers a person will ever
have are present at birth.
 Muscles work by means of two complementary actions:
o Contraction: The shortening of a muscle.
o Extension: The stretching of a muscle.
Types of Muscles:
Smooth Muscles:
 Sometimes called unstriated muscle, is located in such
places as the intestines, and blood vessels.
 Smooth muscles are involuntary because they work
without a person’s conscious control
Skeletal muscles: Are attached to bone and cause body
movements.
 Skeletal muscles are voluntary, under conscious control.
 Work in pairs.
o Flexors: Muscles that close a joint (ex. Bicep)
o Extensors: Muscles that open a joint (ex. Triceps)
Cardiac Muscles: Type of striated muscle that forms the
wall of the heart.
 Pumps blood
 Involuntary Muscle
Muscle Tone: The natural tension in the fibers of a muscle.
 Muscles fibers do not contract at the same time.
 While some are contracting, others are relaxing.
 Constant flow of impulses from nerves maintains muscle
tone.
 Tone is essential for maintaining posture.
 Exercise and good nutrition improves muscle tone.
Problems with the Muscular System:
Muscle Strain: A strain or a “pull muscle” is a sudden,
painful stretching or tearing of muscle fibers.
Muscle Cramp: A cramp occurs when a muscle contracts
spasmodically and involuntarily.
 Feels tense, knotted, and painful
Bruise: Discolored skin that appears after an injury causes
the blood vessels beneath the skin to rupture and leak.
Tendonitis: Inflammation of a tendon caused by an injury,
overuse, or aging.
Hernia: Occurs when an organ or tissue protrudes through
an area of weak muscle.
Muscular Dystrophy: Is a crippling disease characterized
by a progressive wasting away of skeletal muscles.
 Usually inherited
 Muscle cells are unable to function properly and are
replaced by fatty tissue.
 A person may experience muscle weakness, difficulty
standing or walking, or frequent falls.