1. The Systems of the Human Body1

2. Skeletal Muscular Circulatory Nervous Respiratory Digestive Excretory
Review of the 10 Human Body Systems
Skeletal
Muscular
Circulatory
Nervous
Respiratory
Digestive
Excretory
Endocrine
Reproductive
Lymphatic (Immune) 2

3. Homeostasis
from Greek: hómoios, "similar"; and stásis, "standing still“
The ability or tendency of an organism or cell to maintain internal equilibrium by adjusting its physiological processes.

4. You have more than 600 muscles in your body!!
Muscular System
You have more than 600 muscles in your body!!

5. Objectives Identify functions of the muscular system
Identify types and important muscles
Describe how muscles work with bones to create movement
Describe how muscles work like levers
Recall Muscle Diseases & problems

6. Functions of the Muscular System
Provides stability and posture
Motion (walking, swimming, facial expressions..etc.)
Heat Production (shivering)
Aids in circulation &
digestion

7. Major Muscles

8. Tendons
Skeletal muscles are attached to bone by thick bands of tissue called tendons

9. Microscopic Muscle
Muscles are
made of small
muscle fibers

10. Types of muscle Voluntary Involuntary Muscles you can control
Muscles you can’t control
Cardiac & Smooth Muscle
Ex. Heart, muscles that help digest food
Voluntary
Muscles you can control
Striated Muscle
Ex. Bicep, Quadriceps

11. How do muscles work with bones?
*Contraction & Relaxation
*Muscles Work in Pairs
*p. 160

12. Muscles are the body’s Simple Machines
Muscles work like levers
3 Types: 1st Class, 2nd Class & 3rd Class

13. 1st Class
In a first class lever, the weight and force are on opposite sides of the fulcrum:
Examples of this lever include scissors, crowbars, and
teeter-totters.
An example of a first-class lever is the joint between the skull and the atlas vertebrae of the spine: the spine is the fulcrum across which muscles lift the head.

14. 2nd Class
In the second class lever, the load is between the fulcrum and the force:
An example of this lever is a wheelbarrow.
An example in the human body of a second-class lever is the Achilles tendon, pushing or pulling across the heel of the foot.

15. 3rd Class
In the third class lever, the force is between the fulcrum and the load 
Examples of this lever class include: a pair of finger-nail clippers or tweezers.
An example of a third-class lever in the human body is the elbow joint: when lifting a book, the elbow joint is the fulcrum across which the biceps muscle performs the work.