AIM: Why do we need a Muscular system?

DO NOW: Explain how puppets work

HW: Identify the 3 types of muscle and provide examples

of each

LocomotionMovement by contracting (shortening) and relaxing

(expanding) muscles

The Muscular System

A body system of muscles that enable the

organism to perform the life

activity of

Approximately 40% of your body weight is in muscles

You have over 630 muscles that move you. Muscles can't push. They pull.

Muscles often work in pairs so that they can pull in different or opposite directions.

•You have over 30 facial muscles

•Eye muscles are the busiest muscles in the body. Scientists estimate they may move more than 100,000 times a day!

•The largest muscle in the body is the gluteus maximus muscle in the buttocks.

Parts of the Muscular system

1. Muscles organs that contract

& relax to move body parts

Two types:1.Voluntary2.Involuntary

Voluntarymuscles

Muscles that you are able to control

Involuntarymuscles

Muscles that you are NOT able to

control

2. Tendons connective tissue

that connects muscle to bone

Aim: How are our muscles different?

Do Now: Read Contractile Obligation and answer these

questionsHW: textbook page 505 copy and

complete

3 Groups ofMUSCLES

1. Skeletal Muscle

Any muscle that is

attached to the skeleton,Voluntary in

action

Skeletal muscle is striated

Striations appears as stripes on the tissue

2. SmoothMuscle

Muscle that is found in organs,

Involuntary in action

3. CardiacMuscle

Muscle that is found only

in the heart,Involuntary in

action

Contains striations

Fibers are branched

A

B

C

Aim: How do our muscles work?Do Now:

Muscles work by Working in pairs

One contracts while the other relaxes

How domuscleschange

Become larger or smaller

depending on usage.

More exercise causes muscles to be larger in size

Less exercise causes muscles to be smaller in size

Gregg Valentine Before (@ 20 yrs old)

After (Steroid use)

24in arms

In the Gym

27in. arms

AFTER THEY EXPLODED DUE TO BLOOD CLOTS

He went from This to This!

Summary

How do muscles do “all this work”?

•Use energy produced from the life process of ________________•The energy is produced in the __________________

AEROBIC RESPIRATION

MITOCHONDRIA

Why do our muscles get tired?

If you run out of oxygen your body

temporarily switches to Anaerobic Respiration called fermentation

Which produces lactic acid

Lactic acid build up causes muscle fatigue/ muscle cramping

Muscle Fatigue