1. Chapter 14
Human Locomotion

2. In humans, locomotion involves the interaction of:
1. Bones
2. Cartilage
3. Muscles
4. Tendons
5. Ligaments

3. (I) Bones Composed mainly of calcium
Made up of living bone cells and connective fiber tissue

4. Bones provide: Support and protection of body organs
Anchorage for muscles
Leverage for muscles
Bone marrow for the production of blood cells

6. Bone Marrow white blood cells platelets
Found in hollow cavities of bone
These hollow cavities are known as the Haversian canals
Produce:
red blood cells
white blood cells
platelets

7. Where bone meets bone in an organism
Joints
Where bone meets bone in an organism

8. Types of Joints Immovable joint Ball-and-socket joint Hinge joint
Gliding joint

9. Immovable Joint
Bones that are tightly fitted together

10. Ball-and-Socket Joint
Can move in all directions

11. Hinge Joint
Permits back and forth motion

13. Provides limited flexibility in all directions
Gliding Joint
Provides limited flexibility in all directions

14. (II) Cartilage Unlike bone, cartilage is flexible and elastic
Found at joints, nose, and ear
Absorbs shock

15. Ossification
The process by which cartilage gradually changes into bone
Ex: In humans, the skeleton of an embryo is made up of mostly cartilage. By adulthood, most of this cartilage changes into bone by the process of ossification

16. (III) Muscles Three types of muscle: Skeletal muscle Smooth muscle
Cardiac muscle

17. Skeletal Muscle Voluntary (can be controlled) Involved in locomotion
Attached to bone
Striated in appearance (striped)
Function as antagonistic pairs

20. Antagonistic Pairs Muscles work as opposites Ex:
1. Bicep contracts then triceps relaxes
2. Triceps contracts then the bicep relaxes

21. Summary
When the bicep contracts, the arm bends upward (flexes) and therefore the bicep is known as a flexor
When the triceps contracts, the arm extends outward and therefore the triceps is known as an extensor

22. Smooth Muscle Smooth are not striated in appearance
Involuntary (cannot control movement)
Found in:
-walls of digestive organs
-walls of arteries and veins
-walls of internal organs

23. Cardiac Muscle Found only in the heart Striated in appearance
Involuntary

24. (IV) Attachments Ligaments- connect bone to bone
Tendons- connect muscle to bone

25. (V) Disorders of Locomotion
Arthritis- inflammation of the joints
Tendonitis- inflammation of a tendon, usually where it is attached to the bone