Which of the following contains both protons and neutrons?
A. outer shell
B. nucleus
C. covalent bond
D. ionic bond

Ronald wants to see if a new shower cleaner works better in removing soap than his old cleaner. he uses the new cleaner on one half of the shower tiles and his old cleaner on the other half. identify the independent and dependent variables in this experiment. enter your answer in the space provided.

What is the main function of the central vacuole in a plant cell? a. absorbs energy from the sun to produce food b. holds water and maintains turgor pressure c. breaks down molecules to release energy d. contains the cell's genetic material

Hershey and chase confirmed that dna, not protein, was the genetic material. how do the results of their two experiments support this conclusion?