Biology Focus Qs Chapter 8  


  1. Why is life dependent on energy?
  2. Where does the energy that living things need come from?
  3. What is the ultimate source of energy for most living things?
  4. Compare and contrast autotrophs and heterotrophs.
  5. How do mushrooms obtain their energy?
  6. What must organisms do to sugar in order to live?
  7. Describe what happens to the chemical bonds in a candle as it burns.
  8. What is the main source of chemical energy in living things?
  9. Draw a diagram of ATP.
  10.  Look at diagram 8-3.  Explain what is going on regarding ADP/ATP relating to a battery.
  11.  How is the energy in ATP released?
  12.  What is ATP used for in cells?  Give at least 5 specific activities.
  13.  Why do most cells only have a small amount of ATP on hand at any given moment?
  14.  How do cells store energy?  (hint: what biomolecule is used to store energy?)


1. What do plants do during the process of photosynthesis?

2. Briefly describe Van Helmont's experiment and what his conclusions were.

3.  Briefly describe both of Priestley's experiments and what conclusions he made for each one.

4.  Look at the timeline...what did Jan Ingenhousz do and what did he conclude?

5.  Look at the did Melvin Calvin contribute to our understanding of photosynthesis?

6.  Write the equation for photosynthesis.  How does it compare to cell respiration?

7.  Where does the energy input come from that drives photosynthesis?

8.  What is chlorophyll and what is its role in photosynthesis?

9.  What are pigments?  Draw a picture of a red pigment and what is does with light energy (remember that light energy has more than just red light waves, it has all the colors of the rainbow!).

10.  Look at figure 8-5, what light waves does chlorophyll a capture/reflect?  What about chlorophyll b?

11. Why do plants look green?

12.  What are carotenes?  Based on that, explain why carrots were given their name.

13.  What happens to the light energy absorbed by chlorophyll?


1.  What are the light collecting units in a chloroplast?

2.  Where are those light collecting units located in the chloroplast?

3.  Look at Figure 8-7.  Where is the ATP that is generated in the light dependent reaction used?

4.  What is a carrier molecule?

5.  What does NADP+ carry?

6.  What are the high energy electrons used for in a cell?

7.  What happens to e- that absorb light energy?

8.  How are the e- lost from photosystem II replaced?

9.  Look at your notes and at Figure 8-10.  Describe the flow of e- from water to NADPH.

10.  What is generated as e- flow from photosystem II to photosystem I?

11.  Study Figure 8-11.  What are the reactants for the Calvin Cycle (the light independent reaction) and what are the products?

12.  What happens to all the carbons in CO2 in the Calvin Cycle?

13.  What does the plant use the sugars for?

14.  Summarize the main functions of the light dependent and light independent reactions.

15.  What are three factors that affect the rate of photosynthesis?