There are 5 levels of cell organization recognized by biologists.
Answer:
Water based fluid
Explanation:
The internal environment consists of water based fluid in which the cells of the body present. A fluid called interstitial fluid or tissue fluid bathes the cells and provides essential nutrients to the cell. The human skin has fatty layers that helps to maintain internal heat which is produced by the body when the outside environment is cold. When there is cold in the environment, people lives in warm shelters and wear warm clothes in order reduce the impact of cold environment.
Explanation:
Like most stars in our universe, the Sun is on the main sequence stage of its life. This means nuclear fusion reactions in its core fused hydrogen into helium. However, this process cannot last forever since there is a finite amount of hydrogen in the core of the Sun. Currently it has more than 72% hydrogen.