OCR A Level Biology B (Advancing Biology)
OCR A Level Biology B (Advancing Biology) Gas Exchange in Mammals and Plants Exam Questions
Free OCR A Level Biology B (Advancing Biology) exam questions on Gas Exchange in Mammals and Plants, with mark schemes. Covers lungs, ventilation, spirometry, leaves and stomata.
Gas Exchange in Mammals and Plants exam questions
1 question pack of real past exam questions with its mark scheme. Answer every question without notes, then mark your answers line by line against the mark scheme.
StemUp mark scheme flashcards
A Level Biology Flashcards
Every answer is written in mark scheme wording, so you learn exactly what examiners give marks for. Pick your exam board, then test yourself with the questions on this page.
View flashcards
About OCR A Level Biology B (Advancing Biology) Gas Exchange in Mammals and Plants
This topic covers gas exchange in mammals and plants.
What you need to know
- Lungs Alveoli adaptations and ventilation.
- Spirometry Tidal volume, vital capacity and oxygen uptake.
- Leaves Palisade and spongy mesophyll, air spaces.
- Stomata Guard cells control gas exchange and water loss.
Common mistakes in Gas Exchange in Mammals and Plants
- Misreading spirometer traces.
- Saying plants only photosynthesise and do not respire.
- Forgetting stomata close at night.
Try three Gas Exchange in Mammals and Plants exam-style questions
1. Explain how alveoli are adapted for gas exchange. (2 marks)
Show the mark scheme answer
Large surface area (1) and thin walls giving a short diffusion distance (1).
2. State how oxygen uptake is found from a spirometer trace. (1 mark)
Show the mark scheme answer
From the gradient of the downward slope as CO₂ is absorbed.
3. Explain how guard cells open stomata. (2 marks)
Show the mark scheme answer
Ions enter and water follows by osmosis (1), making the cells turgid and curved (1).
Gas Exchange in Mammals and Plants FAQs
What does this topic cover?
Gas exchange in lungs and leaves.
Which practical links here?
Using a spirometer.
Why is soda lime used in a spirometer?
It absorbs exhaled carbon dioxide.
Revise this topic with flashcards: A Level Biology Flashcards, with mark scheme answers for Anki and Quizlet.
