Ultra Violet rays or UV's cause the skin to burn in the sun.
He was talking about you I think it means
The muscular system is made up of over 600 muscles. These include three muscle types: smooth, skeletal, and cardiac. Only skeletal muscles are voluntary, meaning you can control them consciously.
Range of Motion is the measurement of movement around a specific joint or body part. Range of motion (ROM) exercises can help to improve flexibility as well. Making these exercises will increase the range of motion around a joint, referred to as flexibility. In order for a joint to have full range of motion, it must have good flexibility.
Your answer of your question is,
Explanation:
Environment
