Which organelle is responsible for providing a barrier allowing only certain things in and out of the cell?

Conditions affecting the earth's weather

A protein called p53 can keep cells from dividing. To prevent cell division, this protein most likely stops a. respiration b. mitosis c. mutation d. osmosis.

Which of the following example of an ecological study involves the ecosystem level of organization ...

Which of the following describes vicariance? When the Indian subcontinent slammed into Asia forming the Himalayan Mountains, two populations of oak trees were permanently separated by the mountains.

What are the end products of the hydrolysis of a polysaccharide?

Volcanoes, lightning, and the combustion of fossil fuels ALL contribute to acid precipitation. true false

Does an electric current cause a coiled wire to become an electric bell

Which is a renewable resource? A) coal B) sunshine C) gasoline D) natural gas

How are fitness and adaptation important to natural selection?

Where do the light-independent reactions of photosynthesis occur? A. Stroma B. Thylakoids C. Cell cytoplasm D. Intermembrane space