Why does a plant cell have a cell wall and a cell membrene while the animal only a membrane?

Aflashlight produces light using energy from the batteries. in which order does the energy change form? a. from chemical to electric to light energy b. from electric to light to chemical energy c. from electric to chemical to light energy d. from light to electric to chemical energy

The human body needs energy in order to carry out life processes such as breathing. where does the body get this energy? a. from eating food b. from learning about new things c. from lying in the sun d. from sleeping

What are the three different shapes or structures shapes or structure of carbon-based molecules?