AP Biology Unit 3 Review: Cellular Energetics

This AP Bio Unit 3 review brings together everything you need for Cellular Energetics: flashcards, MCQs, FRQs, and click-on challenges for enzymes, cellular respiration and photosythesis.

Contents

  1. Unit 3 Overview Video
  2. Learning Objectives
  3. Flashcards
  4. Multiple Choice Quiz
  5. FRQs
  6. Quiz: Comparing Photosynthesis and Respiration
  7. Cellular Respiration Click-on Challenge
  8. Photosynthesis Click-on Challenge

AP Bio Unit 3 Review Video

1. Unit 3 Learning Objectives

Click the link above for student-friendly learning objectives, aligned to the College Board’s 2025 Course and Exam Description


2. Unit 3 Flashcards

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[h] Unit 3 Cumulative Flashcards

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3. Unit 3 Multiple Choice Review

[qwiz style=”min-height: 450px !important; width: 550px !important;” qrecord_id=”sciencemusicvideosMeister1961-Unit 3 Summative Quiz” use_dataset=”2019 AP Bio Dataset|unit: 3.Cellular Energetics” display_name=”AP Bio Unit 3 Multiple Choice”]

[h] Unit 3 Multiple-Choice Quiz

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4. Unit 3 Cumulative Free Response Quiz

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[h]Unit 3 Cumulative Free Response Quiz

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5. Quiz: Comparing Photosynthesis and Cellular Respiration

Note that to make a point, the diagram that this quiz is based upon takes one liberty: what goes into a mitochondrion (“g”) is pyruvic acid, not glucose (or another simple sugar, indicated by “e”).

[qwiz random=”true” quiz_timer=”true” style=”min-height: 450px !important; width: 550px !important;” qrecord_id=”sciencemusicvideosMeister1961-Comparing Respiration and PSN (2.0)”]

[h] Comparing Photosynthesis and Respiration

[i] If it suits your learning style, use the timer on the top right as a way to improve your accuracy and speed in the questions that follow.

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1716a276dfbb56″ question_number=”1″] In the diagram below, carbon dioxide is indicated by

[textentry single_char=”true”]

[c]IG w=[Qq]

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[c]ICo=[Qq]

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Cg==

[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|171665edaa9356″ question_number=”2″] In the diagram below, oxygen is indicated by letter

[textentry single_char=”true”]

[c]IG Y=[Qq]

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[c]ICo=[Qq]

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[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|17162bb8814f56″ question_number=”3″] In the diagram below, protons are pumped to which region of a chloroplast?

[textentry single_char=”true”]

[c]IG Q=[Qq]

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[c]ICo=[Qq]

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Cg==

[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1715f3d763ef56″ question_number=”4″] In the diagram below, protons are pumped to which region of a mitochondrion?

[textentry single_char=”true”]

[c]IG g=[Qq]

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[c]ICo=[Qq]

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Cg==

[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1715b74e2ec756″ question_number=”5″] In the diagram below, the electron transport chain in a mitochondrion would be found on

[textentry single_char=”true”]

[c]IG k=[Qq]

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[c]ICo=[Qq]

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Cg==

[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|17157f6d116756″ question_number=”6″] In the diagram below, the electron transport chain in a chloroplast would be found on

[textentry single_char=”true”]

[c]IG M=[Qq]

[f]IFllcy4gTGV0dGVyIOKAnGPigJ0gaW5kaWNhdGVzIHRoZSB0aHlsYWtvaWQgbWVtYnJhbmUsIHdoaWNoIGlzIHdoZXJlIHRoZSBlbGVjdHJvbiB0cmFuc3BvcnQgY2hhaW4gaXMgbG9jYXRlZCBpbiBhIGNobG9yb3BsYXN0Lg==[Qq]

[c]ICo=[Qq]

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[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|17152b9b655756″ question_number=”7″] In the diagram below, the Calvin cycle would occur at

[textentry single_char=”true”]

[c]IG I=[Qq]

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[c]ICo=[Qq]

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[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1714e5c2009f56″ question_number=”8″] In the diagram below, the Krebs cycle would occur at

[textentry single_char=”true”]

[c]IG o=[Qq]

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[c]ICo=[Qq]

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[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|17149d94900356″ question_number=”9″] In the diagram below, ATP synthase in a chloroplast would be found at

[textentry single_char=”true”]

[c]IG M=[Qq]

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[c]ICo=[Qq]

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[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|171455671f6756″ question_number=”10″] In the diagram below, ATP synthase in a mitochondrion would be found at

[textentry single_char=”true”]

[c]IG k=[Qq]

[f]IFllcy4gVGhlIGxldHRlciDigJxp4oCdIGluZGljYXRlcyB0aGUgaW5uZXIgbWl0b2Nob25kcmlhbCBtZW1icmFuZSwgd2hpY2ggaXMgd2hlcmUgdGhlIEFUUCBzeW50aGFzZSBjaGFubmVsL2VuenltZSBpcyBmb3VuZCBpbiBhIG1pdG9jaG9uZHJpb24u[Qq]

[c]ICo=[Qq]

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[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|17140ae5a2e756″ question_number=”11″] Pretend that a chloroplast could have a goal (besides reproducing itself). If a chloroplast had a goal, what letter below could best represent it?

[textentry single_char=”true”]

[c]IG U=[Qq]

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[c]ICo=[Qq]

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Cg==

[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1713b96802bb56″ question_number=”12″] Pretend that a mitochondrion could have a goal (besides reproducing itself). If a mitochondrion had a goal, what letter below could best represent it?

[textentry single_char=”true”]

[c]IG s=[Qq]

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[c]ICo=[Qq]

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Cg==

[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1713713a921f56″ question_number=”13″] What letter represents the energy that drives photosynthesis?

[textentry single_char=”true”]

[c]IG 4=[Qq]

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[c]ICo=[Qq]

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Cg==

[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|17132b612d6756″ question_number=”14″] What letter represents the energy that drives cellular respiration?

[textentry single_char=”true”]

[c]IG U=[Qq]

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[c]ICo=[Qq]

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[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1712e587c8af56″ question_number=”15″] In the diagram below, the inputs provided to the Calvin cycle at letter “b” would include ATP and [hangman]

[c]IE5BRFBI[Qq]

[f]IEdvb2Qh[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1712a2026fdb56″ question_number=”16″] In the diagram below, the inputs provided to the Calvin cycle at letter “b” would include NADPH and [hangman]

[c]IEFUUA==[Qq]

[f]IEdvb2Qh[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|17125c290b2356″ question_number=”17″] In the diagram below, which letter indicates the source of the electrons that flow in non-cyclic electron flow?

[textentry single_char=”true”]

[c]IG 0=[Qq]

[f]IFllcy4gTGV0dGVyIOKAnG3igJ0gcmVwcmVzZW50cyB3YXRlciwgd2hpY2ggaXMgdGhlIHNvdXJjZSBvZiB0aGUgZWxlY3Ryb25zIGluIG5vbi1jeWNsaWMgZWxlY3Ryb24gZmxvdy4=[Qq]

[c]ICo=[Qq]

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[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|171218a3b24f56″ question_number=”18″] The structure at “c” is a [hangman] membrane.

[c]IHRoeWxha29pZA==[Qq]

[f]IEV4Y2VsbGVudCE=[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1711d07641b356″ question_number=”19″] The enzyme found in both “c” and “i” that uses the flow of protons to generate ATP is called ATP [hangman]

[c]IHN5bnRoYXNl[Qq]

[f]IENvcnJlY3Qh[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|171185f4c53356″ question_number=”20″] The particles that are pumped into “d” and “h” are [hangman]

[c]IHByb3RvbnM=[Qq]

[f]IEdyZWF0IQ==[Qq]

[q dataset_id=”SMV_PSN_Comparing Photosynthesis and Respiration|1710fc9607a756″ question_number=”21″] The membrane transport process that brings protons from “d” to “b” and from “h” to “j” is [hangman] diffusion

[c]IGZhY2lsaXRhdGVk[Qq]

[f]IEV4Y2VsbGVudCE=[Qq]

[x]

[restart]

[/qwiz]


6. Cellular Respiration Click-On Challenge

[qwiz style=” width: 600px !important; min-height: 400px !important;” quiz_timer=”true” random=”true” spaced_repetition=”false” dataset_intro=”true” use_dataset=”cellular-respiration-click-on-challenge” qrecord_id=”sciencemusicvideosMeister1961-Cellular Respiration Click-on Challenge (2.0)”]

[h] Cellular Respiration Click-On Challenge

[i] Note the timer in the top right corner. In the quiz that follows, aim for accuracy and speed.

[/qwiz]


7. Photosynthesis Click-On Challenge

[qwiz style=” width: 600px !important; min-height: 400px !important;”quiz_timer=”true” use_dataset=”Photosynthesis Click-On Dataset” dataset_intro=”true” spaced_repetition=”false” qrecord_id=”sciencemusicvideosMeister1961-Photosynthesis Click On Challenge (U3, 2.0)”]

[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.

[/qwiz]