Which best explains the importance of a selectively permeable cell membrane? a it prevents bacteria and viruses from entering the cell. b it controls which proteins are synthesized in the cell. c it controls what is allowed to enter or leave the cell. d it prevents the loss of too much water from the cell.

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.

How do living things obtain phosphorus

What is the most abundant vertebrate on earth?