Cells are the basic unit of life. Thus, cells are responsible for maintaining a stable internal environment within living organisms. How do humans continue to maintain a stable internal environment if billions of cells die within their bodies each day?
A.
Exposure to the Sun stimulates cell growth.
B.
Humans need fewer cells as they get older.
C.
The cells must be able to reproduce.
D.
New cells are eaten in the form of food.

After reading the paragraph below, answer the questions that follow. researchers have created a robot that has a very thin leg that is moved by cardiac (heart) cells contracting in unison. the robot, made of a polymer similar to that used in making contact lenses, is bathed in heart cells with supporting cells, which then attach to the robot and provide movement as they contract. all of the cardiac cells working together can cause the robot leg to move in a way that individual cells could not. this is an example of a. emergent properties of cells. b. energy flow through an ecosystem. c. adaptation. d. internal environment regulation.

The following hormone had their receptors in the cell membrane except a-insulin b-tsh c-gh d- cortisol

How does the human body lever work?