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Photosynthesis vs cellular respiration

Photosynthesis stores energy in glucose; respiration releases it.

The common mistake

Thinking plants only photosynthesize and don't respire, or swapping the inputs and outputs.

Instead: Photosynthesis: CO₂ + water + light → glucose + O₂ (chloroplasts). Respiration: glucose + O₂ → CO₂ + water + ATP (mitochondria). Plants do both.

Worked example with Guide me

Which gas does a plant release at night?

  1. Sugar · Can it photosynthesize without light?
    Student · No.
  2. Sugar · Is it still respiring?
    Student · Yes, all the time.
  3. Sugar · What does respiration release?
    Student · Carbon dioxide.

Answer: Carbon dioxide

Try 3 practice questions

  1. 1. Where does photosynthesis happen?

    Show answer

    Chloroplasts

  2. 2. What molecule does respiration make for energy?

    Show answer

    ATP

  3. 3. Name the two products of photosynthesis.

    Show answer

    Glucose and oxygen

Quick answers

What is the most common mistake with photosynthesis vs cellular respiration?
Thinking plants only photosynthesize and don't respire, or swapping the inputs and outputs.
How do I get photosynthesis vs cellular respiration right?
Photosynthesis: CO₂ + water + light → glucose + O₂ (chloroplasts). Respiration: glucose + O₂ → CO₂ + water + ATP (mitochondria). Plants do both.
Can you show a worked example?
Which gas does a plant release at night? Carbon dioxide

Related concepts

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