Why does photosynthesis require water? a. because water provides oxygen atoms. b. because water provides electrons. c. because water accepts electrons. d. because water acts as a catalyst.

In a biological reaction involving an enzyme, what does not directly participate in the reaction? the active site of an enzyme the active site of the substrate the inactive site of the substrate the reactant chemicals

3. What is the structural difference between ATP and ADP? Compare/contrast structure of ATP & ADP

If the heterotrophs in level 2 of a trophic pyramid produce 20,000 kilograms of biomass, how much energy did the autotrophs produce? A 20 kg B 200 kg C 2,000 kg D 200,000 kg

Which type or types of rock can become metamorphic rock?

Roshan describes the basic parts of an electric circuit using a shower as a model. which part of a circuit does the water pipe represent? the wire the switch the battery the resistor

4. A tree dropping its leaves in the fall to conserve water and avoid freezing during winter is an example of?

Which is a single-celled fungus? A. mold B. mushroom C. alga D. yeast

Explain problems with using low-tar, low-nicotine cigarettes.

Some students are comparing the parts of a cell to the parts of the body. Which part best represents the cell membrane and why?

What is the difference between the nitrogen and carbon cycles?