Muscles
Science: KS3, topic 1.6.4
Muscles
Muscles have evolved to help with a variety of functions. The human body actually contains many different types of muscle tissue.
Role of muscle
- Some of the roles played by muscles in humans include:
- Locomotion (movement) of the body.
- Release and movement of liquids and digested food.
- Directing of the blood.
Antagonistic pairs
- Muscles are only able to contract (pull) and relax.
- For this reason, you need muscles in antagonistic pairs.
- That is, one muscle moves part of your body one way and the other muscle moves the same body part in the opposite direction.
Triceps and biceps
- The triceps muscle is on the back of your upper arm. It causes your arm to extend.
- The biceps muscle is on the inside of your upper arm. It causes your arm to bend.
- The triceps and biceps are an antagonistic pair because each of them moves the arm in the opposite direction.
Quadriceps and hamstrings
- The quadriceps is above the knee on the front of your leg.
- It extends your leg.
- The hamstring is above the back of your knee.
- It bends your leg at the knee.
- The quadriceps and hamstring oppose each other, and so are an antagonistic pair.
Test yourself on Muscles
What is not a role of muscle in the human body?
Which of these is true of the following muscles?
If the triceps stayed contracted and could not relax, what would happen to the arm?
Food moves along the gut after a person eats. What role of muscle makes this possible?