1. Do Now: What are the functions of muscles?
What are the 3 types of muscles?
What connects muscle to bone?
What kind of joint is in your elbow?
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2. How our Muscles Work Muscles work by
CONTRACTING (getting shorter and fatter) and pulling on bones.
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3. How our Muscles Work
Muscles are attached to bones by strong non-stretchy TENDONS.
muscle
tendons
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4. Our Achilles tendon in our heel
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5. How our Muscles Work
A muscle’s ORIGIN is the end attached to the bone that doesn’t move.
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6. How our Muscles Work
The INSERTION is the end attached to the bone that is moved when the muscle contracts. .
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7. How our Muscles Work
But once contracted, a muscle cannot RELAX again by itself.
Each muscle needs a partner.
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8. How our Muscles Work
Two muscles working together in opposite directions are called
ANTAGONISTIC muscles.
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9. How our Muscles Work
The BICEPS and TRICEPS in our arm are an ANTAGONISTIC PAIR. They work as a pair and in opposite directions.
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10. Bending our Arm TRICEPS relaxes and is pulled longer
BICEPS contracts and bends arm
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11. Straightening our Arm BICEPS relaxes and is pulled longer
TRICEPS contracts and straightens arm
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12. Part of Antagonistic Pairs
. The PRIME MOVER is the muscle that contracts and the ANTAGONIST is the muscle that relaxes.
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13. Part of Antagonistic Pairs
When you move your arm up, your triceps relaxes. The biceps is the PRIME MOVER, and the triceps is the ANTAGONIST.
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