ATP: the cell's energy carrier

Grade 9 Science Worksheet - Building Confidence

Circle the best answer.

1. Read this first

   Use this

   Flow diagram (model, not to scale), drawn inside the cell. Inputs in boxes on the left. Outputs in boxes on the right.

2. 1.

   Ari reads a diagram of ATP being broken down. Box A holds adenosine with two phosphate groups. What is A?

   • ATP, with three phosphate groups
   • AMP, with one phosphate group
   • ADP, with two phosphate groups
   • ADP, with three phosphate groups

3. Use this

   Flow diagram (model, not to scale), drawn inside the mitochondrion. Inputs in boxes on the left. Outputs in boxes on the right. A wavy arrow points into the reaction.

4. 2.

   Bo reads a diagram of ATP being rebuilt inside a mitochondrion. Box B is one separate phosphate group. What is B called?

   • Adenine, a nitrogenous base
   • ADP, adenosine with two phosphates
   • Pi, an inorganic phosphate group
   • Ribose, a five-carbon sugar
5. 3.

   Esme reads a diagram of ATP being rebuilt in a chloroplast, with light shining on it. What does wavy arrow C show?

   • Energy that ADP and Pi make by themselves
   • Energy that ATP gives off as it is rebuilt
   • Energy released when the third phosphate joins
   • Energy from light that is used to rebuild ATP

6. Use this

   Flow diagram (model, not to scale), drawn inside the cell. Inputs in boxes on the left: ATP: adenosine joined to a row of 3 phosphate circles. No output boxes are drawn. No wavy arrow label is drawn.

7. 4.

   Jun counts the circles in the drawing of ATP. Each circle is a phosphate group. How many phosphate groups does ATP have?

   • 3 phosphate groups
   • 4 phosphate groups
   • 1 phosphate group
   • 2 phosphate groups

8. Use this

   Flow diagram (model, not to scale), drawn inside the cell. Inputs in boxes on the left: ATP: adenosine joined to a row of 3 phosphate circles. Outputs in boxes on the right: ADP: the same drawing with 1 circle fewer; Pi: 1 circle on its own. A wavy arrow points out of the reaction: energy released.

9. 5.

   Kira compares ATP with ADP in the diagram. ADP is drawn with 1 circle fewer than ATP. How many phosphate groups does ADP have?

   • 2 phosphate groups
   • 3 phosphate groups
   • 4 phosphate groups
   • 1 phosphate group

10. Use this

    Flow diagram (model, not to scale), drawn inside the cell. Inputs in boxes on the left: 4 ATP molecules. Outputs in boxes on the right: 4 ADP molecules; the separate Pi groups, one from each ATP. A wavy arrow points out of the reaction: energy released.

11. 6.

    Luz sees 4 ATP molecules broken down, each into one ADP and one Pi. How many Pi groups come off in all?

    • 4 Pi groups
    • 12 Pi groups
    • 8 Pi groups
    • 1 Pi group
12. 7.

    Milo reads that ATP breaks down by hydrolysis. Which phrase tells what hydrolysis means in the diagram?

    • Breaking a bond to create new energy
    • Using ATP up so it is gone for good
    • Breaking a molecule apart by adding water
    • Joining ADP and Pi back into ATP
13. 8.

    Noah reads that ATP is the cell's energy currency, like coins. What does the comparison mean?

    • Cells spend each ATP once, and it is gone
    • Cells save ATP for years, like coins in a bank
    • Cells spend ATP's energy on work, then rebuild ATP
    • Cells print new ATP at no energy cost

14. Use this

    Flow diagram (model, not to scale), drawn inside the cell. No wavy arrow label is drawn. Letter D marks a wavy arrow touching the reaction; its label is blank.

15. 9.

    Ren sees ATP and water turn into ADP and Pi, with a blank wavy arrow D. Which label fits D?

    • Energy out: made new as the bond breaks
    • Energy out: released for cell work
    • No energy moves: ATP and ADP hold equal energy
    • Energy in: added to break ATP down
16. 10.

    Flow diagram (model, not to scale), drawn inside the cell. No wavy arrow label is drawn. Zee reads where a cell's energy from glucose can go. Which box is the long-term store of energy?

    • Neither, since cells cannot hold energy
    • Both, since ATP lasts as long as starch
    • Box H, the chain of stored glucose
    • Box G, the ATP that is ready to use