Answer:
Muscles move body parts by contracting and then relaxing. Muscles can pull bones, but they can't push them back to the original position. So they work in pairs of flexors and extensors. The flexor contracts to bend a limb at a joint.
Explanation:
Answer:
If air is polluted, the air contains harmful gases and health status become poor. In contrary, if environment is clean and fresh, the health will be good. Therefore, health, population and environment education are interrelated in physical aspect. Health, population and environment are integrated terms.
I think it's fast twitch fibers, others will say myosin, but when I took the quiz, it marked myosin wrong