K325 / 2027

Chapter 6 / 6 short lessons

Respiration in humans

Connect breathing and gas exchange to energy release in cells, including exercise and recovery.

G3 Pure Biology / K325 / 2027 syllabus

What do you think?

A runner stops, but keeps breathing quickly. What still needs explaining?

Lessons

0 of 6 marked as read
01

Follow air into the lungs

Identify the airway structures, exchange surfaces and the role of cilia.

About 4 min
About 4 min
02

How breathing moves air

Explain inhalation and expiration through muscle action, chest volume and air pressure.

About 5 min
About 5 min
03

Exchange gases at an alveolus

Link alveolar structure and blood supply to efficient diffusion.

About 5 min
About 5 min
04

Link smoke components to effects

Explain the major biological effects of the three named tobacco-smoke components.

About 4 min
About 4 min
05

Aerobic respiration releases energy

Define aerobic respiration and use its word and balanced symbol equations.

About 5 min
About 5 min
06

Anaerobic respiration and recovery

Explain anaerobic energy release, lactic acid and repayment of an oxygen debt.

About 5 min
About 5 min
What you will be able to do
  • Trace air to the exchange surface.
  • Explain ventilation using muscles, volume and pressure.
  • Connect alveolar structure to diffusion.
  • Use respiration equations and explain recovery after exercise.

Ready to try it without your notes?

Start with a quick check or explain a biological result in your own words.

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