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Comparing Photosynthesis and Respiration 4 questions

Comparing Photosynthesis and Respiration

New Regents original practice • Name: ____________________ Date: __________ Show your work for written answers.

In a simplified model, photosynthesis uses CO2 and H2O plus light to make glucose and O2. Aerobic respiration uses glucose and O2 to make CO2 and H2O and releases energy that cells can use.

Question 1

Which substance is a product of photosynthesis and a reactant in aerobic respiration?

  1. Glucose
  2. Carbon dioxide
  3. Water
  4. Light

Question 2

Compare the energy roles of the two processes.

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Question 3

Which process returns carbon from glucose to carbon dioxide in the simplified model?

  1. Photosynthesis
  2. Aerobic respiration
  3. Both consume carbon dioxide.
  4. Neither process involves carbon.

Question 4

A plant in bright light produces oxygen and also consumes it. Explain how both can happen.

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Tracking Oxygen in a Model 4 questions

Tracking Oxygen in a Model

Use the information below to answer the questions.

The model counts O2 made by photosynthesis and O2 used by respiration over equal intervals. The net oxygen change is the amount made minus the amount used.

SettingO2 made (units)O2 used (units)
Bright124
Dim54
Dark04

Question 5

Which setting shows the largest net oxygen gain?

  1. Bright
  2. Dim
  3. Dark
  4. All three are equal.

Question 6

Calculate the net oxygen change in the dark setting. Include the sign.

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Question 7

Which quantity is constant across all three rows?

  1. Oxygen production
  2. Oxygen use by respiration
  3. Net oxygen change
  4. Light level

Question 8

The dim setting has a net gain of only one unit. Explain why that does not mean photosynthesis produced only one unit.

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