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
Locomotion Movement 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.Voluntary 2.Involuntary
Voluntary muscles Muscles that you are able to control Involuntary muscles 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 questions HW: textbook page 505 copy and complete
3 Groups of MUSCLES 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. Smooth Muscle Muscle that is found in organs, Involuntary in action
3. Cardiac Muscle 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 do muscles change 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