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Respiration and Gas Exchange

3 dot points across 3 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

How do cells release the energy in food, and what changes when there is no oxygen?

Define respiration, write word equations for aerobic and anaerobic respiration, and compare the energy they release
A scaffolded answer to the N(A)-Level Biology outcome on respiration. What respiration is, the word equations for aerobic and anaerobic respiration in humans and yeast, and how much energy each releases.
7 min answer →

How do the alveoli swap oxygen for carbon dioxide between the air and the blood?

Explain how gas exchange happens in the alveoli and describe how they are adapted for fast diffusion
A scaffolded answer to the N(A)-Level Biology outcome on gas exchange. How oxygen and carbon dioxide diffuse between the alveoli and the blood, and the four adaptations that make the alveoli efficient at this.
7 min answer →

How does air get into and out of the lungs when we breathe?

Describe the parts of the human breathing system and explain how breathing in and breathing out happen
A scaffolded answer to the N(A)-Level Biology outcome on the breathing system. The path of air to the lungs, the role of the ribs and diaphragm, and how the chest changes shape to breathe in and out.
7 min answer →