anatomy & physiology the human body. body organization what’s the smallest unit of life?...

Anatomy & Physiology

The Human Body

Body OrganizationWhat’s the smallest unit of life?

CellHuman Body: 100 trillion cells

Cells tissues organs organ systems organisms

Body Organization (cont.)

Levels of Organization

Skeletal SystemBones:22 skull27 hand26 foot

Skeletal System (cont.)

# of bones:Adults 206Babies 300

Two Divisions:–Axial skeleton:

Includes: skull, vertebrae, sternum, ribs, hyoid bone

–Appendicular skeleton:Includes: pectoral and pelvic girdles, bones of the arms, forearms, wrists, hands, thighs, legs, and feet.

Skeletal System (cont.)

Axial Skeleton

Appendicular

Skeleton

Bone Structure

Bone cells are living!– Osteocytes

Bone contains nerves, blood vessels &

marrow

Bone Classification:Long Bones

–Ex. Arm and leg bonesShort Bones

–Wrist bones Flat Bones

–Make up the skull Irregular Bones

–Facial bones or vertebrae

Compact & Spongy Bone

Dense & strongProvides strength & protection

Outermost part of the bone

Compact Bone:

Less dense & contains bone marrow

Found in short, flat, and long bones

Surrounded by compact bone

Spongy Bone:

Bone Marrow-thick & jelly like

- Yellow- stores fat

-Red- makes blood cells

Bone Structure (cont.)

Ends of Bones are lined with dense tissue: cartilage

Cushions bones Provides support

Bone Structure (cont.)

Tendons: Tough fibers that connect muscle to bone

Bone Structure (cont.)

Ligaments: Tough fibers that connect bone to bone

Bone Structure (cont.)

Function of Bones

1. Support – provides framework for the body

2. Protection – for the brain, spinal cord, and vital organs

3. Movement – lever for muscle

4. Attachment – tendons connect muscle to bone

Function of Bones (cont.)

5. Blood Cell Production occurs in bone marrow

6. Mineral Storage Calcium & Phosphorus

Function of Bones (cont.)

Bone Connections

Fixed Joint (Sutures)

Connects plate-like bones of the skull

Hinge Joint

Allows movement in two directions (Front & Back)

Ex. Elbow, Knee

Ball & Socket Joint

Allows full range of motion

Ex. shoulder

Cracking KnucklesSpace between joints widen

Air bubble forms in the synovial fluid (joint lubricant)

Bubble bursts and makes cracking sound

Skeletal Conditions

BursitisScoliosisOsteoporosis

ArthritisSprainFracture

Bursitis

Inflammation of the bursa (sac)

Curvature of the spine

Scoliosis

OsteoporosisInefficient bone replacement

5-10% of bone mass lost every 10 years past age of 40

Rate of bone eating cells exceeds bone building cells!

ArthritisJoint inflammation

Lose strength & functionEx. Rheumatoid arthritis

SprainOver stretching of ligaments or tendons

Torn ligaments require surgery

FractureBroken bone

Multiple types:–Simple–Compound

–Stress

Simple fracture:–Bone breaks but does not come through the skin

Types of Fractures:

Compound fracture:–Bone protrudes through the skin

Types of Fractures:

Stress fracture:–A thin crack in the bone

Types of Fractures: