1. THE MUSCULAR SYSTEM (Section 2)

2. NAME ONE TYPE OF MOVABLE JOINT
WARM-UP
Complete the BONES QUIZ
BONUS QUESTION! (WORTH ONE POINT)
NAME ONE TYPE OF MOVABLE JOINT

3. MUSCLES A MUSCLE IS AN ORGAN THAT CAN RELAX AND CONTRACT
PROVIDES THE FORCE TO MOVE YOUR BODY PARTS
VOLUNTARY MUSCLES: Muscles that you are able to control
INVOLUNTARY MUSCLES: Muscles that you cannot control

4. 3 TYPES OF MUSCLES Move bones The most common type of muscle
1. SKELETAL MUSCLES
Move bones
The most common type of muscle
TENDONS are thick bands of tissue
that attach muscle to bones.
Voluntary muscles
Contract quickly and tire more easily
Look striped, or Striated (STRI ay tud)

5. 2. CARDIAC MUSCLE Found only in the HEART Is striated, like the
Skeletal Muscles

6. 3. SMOOTH MUSCLES Found in: Involuntary muscles
Intestines
Bladder
Blood vessels
Other internal organs
Involuntary muscles
They work without you thinking about it
Non-striated muscles (not striped)
Contract and relax slowly

7. STRIATED MUSCLE (Skeletal and Cardiac) NON STRIATED MUSCLE (Smooth)

8. Other key points to know:
SKELETAL MUSCLES work together to make you move
When one muscle of a pair CONTRACTS, the
other RELAXES
Muscles always pull
Muscles become larger or smaller over time
Depends on whether or not they are used!
Used muscles= BIGGER
Unused muscles= SMALLER
Blood carries energy-rich molecules to the muscle
Lets them do their work

9. In summary… Muscles help you move! They attach to bones with TENDONS
Involuntary vs. Voluntary Muscles
Striated vs. Non-striated
Three types:
Skeletal
Cardiac
Smooth

10. We have more than 630 muscles in our body.
FUN FACTS!
We have more than 630 muscles in our body.

11. More than 30 of our muscles are in our face – that’s how we can make different expressions (happy, sad), talk and move our eyes around!

12. Scientists estimate that our eye muscles move more than 100,000 times a day!

13. STREET GYMNAST
WHAT MUSCLES LOOK LIKE

14. Your muscles need Glycogen (muscle sugar) in order to function
Your muscles need Glycogen (muscle sugar) in order to function. When the glycogen is broken down into energy for the muscles a waste product called lactic acid is produced. A buildup of lactic acid decreases the muscles’ ability to contract and Muscle Fatigue sets in. DO THIS: Hold a book in each hand. Raise one arm straight out parallel to the ground and the other arm down at your side. Compare the feeling in each arm... **keep track of how long you can hold the books for and which arm gets tired faster!

15. How long did you hold the book before fatigue got the better of you?
________ minutes ________ seconds
Which arm felt the fatigue the most?
The straight arm or the arm by your side?
Which muscles experienced the most fatigue?
Biceps triceps deltoids pectoralis major