1. Unit 10 Chapter 34 Protection, Support, and Locomotion

2. Skin: the Body’s Protection
Integumentary System
Contains skin and its related parts—hair, nails & glands
Functions:
Regulates body temperature
Receives stimuli from environment
Produces vitamin D
Protection of underlying tissues

3. Skin: the Body’s Protection
Epidermis:
Outer layer of skin, composed of dead, flattened cells
Contains Melanin, a pigment that colors the skin & protects cell from damage by radiation

4. Skin: the Body’s Protection
Dermis
Inner, thicker portion of the skin
Contains blood vessels, nerve endings, hair follicles, sweat & oil glands

5. Skin: the Body’s Protection
Hypodermis (subcutaneous layer)
Below the dermis
Contains primarily of fat for cushioning & insulation

6. Bones: the Body’s Support
Skeletal System divisions:
Axial skeleton
Includes the skull, vertebrae, ribs & sternum
Appendicular skeleton
Includes bones of the arms & legs, and shoulder & hip bones

7. Bones: the Body’s Support
Skeletal system functions:
Protection
Support
Attach muscles
Produce blood cells
Store minerals

8. Bones: the Body’s Support
Joints
Where two bones meet
Facilitates the movement of bones in relation to one another

9. Bones: the Body’s Support
Ligaments
Connective tissue that attaches one bone to another
Tendons
Connective tissue that attach muscles to bones

10. Bones: the Body’s Support
Spongy bone
Soft bone containing many spaces filled with red marrow
Compact bone
Dense bone with an inner cavity containing yellow marrow
Haversian system
Circular area in compact bone containing blood vessels, nerves, and living cells called osteocytes

11. Muscles for Locomotion

12. Muscles for Locomotion
Smooth muscle
Involuntary movement
Found in hollow body organs, i.e. stomach, arteries, iris of eye
Spindle-shaped cells, non-striated, one nucleus per cell

13. Muscles for Locomotion
Cardiac muscle
Involuntary movement
Found only in the heart
Branching, striated (striped) cells, with one nucleus per cell

14. Muscles for Locomotion
Skeletal muscle
Voluntary movement
Found attached to bones, i.e. biceps, triceps, hamstrings, etc
Long, striated (striped) cells, with many nuclei

15. Extensor and flexor muscles
Click on image to play video.

16. Muscles for Locomotion
Common
Skeletal
muscles

17. Muscles for Locomotion
Muscle contraction:
Muscle fibers (cells) are made up of smaller units called myofibrils
Myofibrils contract (shorten) as filaments, called myosin & actin, slide toward one another

18. Sliding filament model