1. You’ll see credit for completing this quiz in “Unit 3 Cumulative Assessment.”
  2. This same quiz can be completed for the same credit on the Biomania AP Bio App. Click here to download Biomania (free for students enrolled in a course with a teacher using

[qwiz quiz_timer=”true” qrecord_id=”sciencemusicvideosMeister1961-Photosynthesis Click On Challenge (U3, 2.0)” dataset=”Photosynthesis Click-On Dataset” dataset_intro=”false” spaced_repetition=”false” style=”width: 600px !important; min-height: 450px !important;”]

[h] Quiz 1: Photosynthesis Click-On Challenge

[i] Note the timer in the top right. The goal is speed and accuracy. A good strategy is to take your time the first time through, carefully looking at the feedback statements. Then work at increasing your speed.

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|7a5b16b2e984″ question_number=”1″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: The two phases of photosynthesis (Light Reactions)


Excellent: “2” is water.

HINT: This is the input of matter for the light reactions.
A stack of thylakoids carrying out the light reactions

Nice. “I” represents the a stack of thylakoids carrying out the light reactions.

HINT: Find a thylakoid that’s carrying out a variety of reactions, powered by light.
Thylakoid sacs that aren’t being stimulated by light.

Way to go!

HINT: The thylakoids are disk-like structures, stacked on top of each other. Find the ones that ARE NOT being stimulated by light. 
The stroma

Good. The stroma is like the cytoplasm of the chloroplast.

HINT: It’s everything inside the membrane, and outside of the thylakoids.

Good job. “3” represents oxygen.

HINT: Oxygen is the waste product of the light reactions. 
NADPH (assume “4” is ATP)

Nice! If 4 is ATP, then “5” is NADPH.

HINT: ATP (4) is one of the products of the light reactions. This is the other one.

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|734c52a7c984″ question_number=”2″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: The two phases of photosynthesis (Calvin Cycle)

Carbon dioxide

Terrific. “6” is carbon dioxide.

HINT: Carbon dioxide is the outside input for the Calvin cycle. 

Nice! “7” represents carbohydrate.

HINT: Carbohydrate is what the Calvin cycle produces . 
Inorganic phosphate

Way to go! “10” is inorganic phosphate.

HINT: “4” is ATP, and 9 is ADP.
The Calvin Cycle

Yes! “II” is the Calvin cycle

HINT: It’s the cycle that converts carbon dioxide (at “6”) into carbohydrates (at “7.”)
ATP (assume 9 is ADP)

Good! “4” is ATP.

HINT: ATP is one of the products of the light reactions (at “I”) and it’s made from ADP and phosphate (“9” and “10”).

Nice! “3” is oxygen.

HINT: Oxygen is a waste output of the light reactions, which are at “I.”

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|6ba3e38be184″ question_number=”3″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: The two phases of photosynthesis (light reactions and carbon fixation).

Carbon fixation

Yes! The Calvin cycle does carbon fixation.

HINT: Look for a process that takes carbon dioxide and makes it into carbohydrate.

Nice. The light reactions create ATP, in a process powered by light

HINT: In what process is ATP being created?
Light-powered creation of ATP and NADPH.

Excellent. The light reactions use light to create ATP (and NADPH)

HINT: You’re looking for the light reactions.

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|5bb25e1f9d84″ question_number=”4″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis” show_hotspots=””] TOPIC: The Z-scheme (processes, parts)

Photosystem II’s antenna complex

Excellent. Letter “a” is the antenna complex for photosystem II.

HINT: The antenna complex traps light…and remember that PS II comes before PS I.
Oxidation of water

Nice job. The oxidation o f water is shown at letter “d.”

HINT: The oxidation of water is what supplies electrons to photosynthesis.
Photophosphorylation of ADP to ATP

Nice! Photophosphorylation (light-powered creation of ATP) is shown below letter “f.”

HINT: Photophosphorylation is the light-powered creation of ATP, and it happens in Photosystem II.
Antenna complex for Photosystem I

Way to go! Letter “o” represents Photosystem I’s antenna complex.

HINT: This is what absorbs light energy into photosystem I (which comes after Photosystem II)
Light-powered creation of NADPH.

Awesome. Letter “K” shows NADP+ getting reduced to NADPH

HINT: This happens at the end of Photosystem I.

Reduction of an electron carrier that’s used in the Calvin Cycle.

Excellent! “L” shows reduction of NADP+ to NADPH.

HINT. This is a process that’s connected to Photosystem 1.

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|56341211ad84″ question_number=”5″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: The Z-scheme (electron flows)

Light-powered electron boosting in PS II.

Excellent. The arrow above “c” shows electron boosting in PSII.

HINT: The circle with an e represents and electron, and PSII comes first.
Light-powered electron boosting in PS I.

Nice job. The yellow arrow above “p” represents electron boosting in PS I.

HINT: The circle with an e represents and electron, and PS I comes second.
PS II’s electron transport chain

Good job. Letter “f” represents the electron transport chain of PS II. 

HINT: PS II comes first, and the symbol e represents an electron.
PS I’s electron transport chain.

Good work! Letter “J” represents the electron transport chain of PS I. 

HINT: PS I comes second, and the symbol e represents an electron. 

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|49b2a6341184″ question_number=”6″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: Thylakoid structure


Excellent. The solution outside of the thylakoid is the stroma.

HINT: The stroma is the solution outside of the thylakoid. It’s like the matrix of a mitochondrion, or the cytoplasm of the cell.
The region with the lowest pH

Nice! The thylakoid space has the lowest pH

HINT: The area with the highest concentration of protons will have the lowest pH.


Channel and Enzyme that makes ATP.

Great job. ATP Synthase is a channel and an enzyme that makes ATP.

HINT: Find a channel that’s letting protons flow from high to low concentration. That’s what powers ATP synthesis at the ATP synthase channel.
The part that converts light to electricity

Awesome. You’ve clicked on a photosystem’s antenna complex.

HINT: Look for a photosystem. It contains the green pigment chlorophyll.

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|406972c7bd84″ question_number=”7″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: The Calvin Cycle (phases)

Carbon fixation  phase

Excellent. Area “I” is the carbon fixation phase

HINT: Find the phase where an enzyme combines CO2 with a 5 carbon molecule.
Energy investment and harvest phase

Nice. Area “II” represents energy investment and harvest

HINT: Look for a phase where ATP and NADPH are energizing 3-carbon molecules, one of which leaves the cycle.
Regeneration of RuBP Phase

Way to go. Phase III represents regeneration of RuBP.

HINT: RuBP is a 5-carbon molecule. To get 3 RuBPs a chloroplast needs to rearrange 5  G3Ps (a 3-carbon molecule).

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|37ef777dad84″ question_number=”8″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: The Calvin Cycle (key molecules)

Carbon dioxide

Nice! Letter “a” represents carbon dioxide.

HINT: Carbon dioxide has one carbon and two oxygens. Use the legend on the top left to find it.
G3P (glyceraldehyde 3-phosphate)

Fabulous. Letter “D” represents G3P.

HINT: Look for a 3 carbon molecule that gets harvested from (leaves) the cycle.
RuBP (Ribulose Bisphosphate)

Nice! Letter “f” represents RuBP

HINT: Look for a 5 carbon molecule that’s made by recombining 3-carbon molecules.

[q json=”true” xx=”2″ dataset_id=”Photosynthesis Click-On Dataset|295b31090184″ question_number=”9″ hotspot_user_interaction=”label_prompt” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: The Calvin Cycle (enzymes and products)

The enzyme that carries out carbon fixation

Excellent! Rubisco (the large enzyme in the right side of phase I) is the enzyme that carries out carbon fixation.

HINT: Look for what looks like a large, complex protein.
The immediate product of carbon fixation.

Awesome. The molecule at “b” is the immediate product of carbon fixation.

HINT: Carbon dioxide (“a”) gets combined with RubP (“f”). What results?
What plant cells harvest from the Calvin Cycle

Good! Plant cells harvest G3P, the 3-carbon molecule at “d.”

HINT: Look for a 3 carbon molecule that’s been energized by ATP and NADH.

[q json=”true” hotspot_user_interaction=”label_prompt” dataset_id=”Photosynthesis Click-On Dataset|37921f2da1666″ question_number=”10″ unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: Light Reactions: Key Components

Photosystem II


HINT: Photosystem II comes BEFORE Photosystem I.
A proton pump.

Outstanding! “C” is a proton pump.

HINT: Protons are getting pumped from low concentration in the stroma to high concentration in the thylakoid space.
Photosystem I

Nice Going. Letter “e” represents Photosystem I.

HINT: Photosystem I is the second photosystem. It powers reduction of NADP+ to NADPH.
ATP Synthase

Great! Letters “i” and “h” represent ATP synthase.

HINT: This enzyme is also a channel that lets protons diffuse from the thylakoid space to the stroma. This diffusion powers ATP synthesis.

[q json=”true” hotspot_user_interaction=”label_prompt” dataset_id=”Photosynthesis Click-On Dataset|3244b819674c5″ question_number=”11″ show_hotspots=”” unit=”3.Cellular_Energetics” topic=”3.5.Photosynthesis”] TOPIC: Light Reactions: Products