Respiration 2.8

Respiration is one of the seven characteristics of all living things and it is essential for life. This topic covers the basics of aerobic and anaerobic respiration. It is important to know what the role of ATP is in cells and also to have experience of using a respirometer to measure the rate of respiration.

Key concepts

Learn and test your biological vocabulary for 2.8 Respiration using these flashcards.

Essentials

These slides summarise the essential understanding and skills in this topic. 
They contain short explanations in text and images - good revision for all students.

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Summary

Summary list for topic 2.8 Respiration

  • Cell respiration definition,"the controlled release of energy from organic compounds to produce ATP"
  • ATP produced is a source of energy ready for immediate use in the cell.
  • Anaerobic cell respiration gives a small yield of ATP from glucose compared to aerobic respiration whose yield is large.
  • Aerobic cell respiration also requires oxygen.
  • Substrates (e.g. glucose) and final waste products (e.g. water, CO2, lactate, ethanol) should be known.
  • Anaerobic cell respiration in yeasts is used to produce ethanol and carbon dioxide in baking.
  • In the human body anaerobic respiration is used to maximise the power of muscle contractions & produces lactate.
  • Know how to use simple respirometers to measure the rate of respiration.
    • to know that an alkali is used to absorb CO2 produced in respirometers, so that reductions in gas volume are due to oxygen use.
    • To keep the temperature constant, so that gas volumes don't change through expansion / contraction of gas.

Mindmaps

This diagram summaries the main sections of topic 2.8.
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Exam style questions

Exam style question about measuring respiration

Understanding measurements of respiration from experiments with respirometers is an important skill from this topic.

Answer the question below on a piece of paper, then check your answer with the model answer below.

The graph shows the results of an experiment with germinating seeds.

Explain how the respirometer apparatus is used to measure the rate of respiration in germinating seeds. [2]

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Calculate the rate of respiration in seeds at 30°C, in cm per minute. [2]

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Extra exam style question about respiration and bread making click on the + symbol to open it.

Exam style question about bread making.

The rising of dough in bread making is an example of anaerobic respiration.

This question requires knowledge of yeast respiration in bread production.

Outline the role of yeast in the production of bread. (3 marks)

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Examiner's hint: "Outline" means give a brief account, including the most important points.

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Test yourself

This is a self marking quiz containing questions covering the topic outlined above.
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Drag and drop activities

Test your ability to construct biological explanations using the drag and drop questions below.

Test your construction of biological knowledge using the drag and drop questions below.

Contrasting aerobic and anaerobic respiration

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large cytoplasm ethanol water small amount Aerobic mitochondrion partially carbon dioxide oxygen completely

respiration begins in the cytoplasm and is completed in the . It uses oxygen, breaks down glucose into and and produces a amount of ATP energy.

Anaerobic respiration occurs in the . It does not use and breaks down glucose into or lactic acid and produces a of ATP energy.

Examiner hint: In any compare or compare and contrast response you should use a point of comparison per sentence e.g. aerobic respiration uses oxygen; anaerobic does not. The above paragraphs are written for the drag and drop activity.


Just for fun

This is a little bit of fun. You can choose your favourite game but I prefer the word shoot! Respiration word shoot game

MY PROGRESS

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