2.8 Cell respiration

Essential idea: Cell respiration supplies energy for the functions of life.

Energy in cells is all about the molecule above, Adenosine Triphosphate (ATP). The energy is held in the bonds between atoms, in particular the high energy bond that joins the second and third phosphates. ATP is the energy currency of the cell. Hence the efficiency of respiration is measured by the yield of ATP

Understandings, applications and skills

2.8.U1	Cell respiration is the controlled release of energy from organic compounds to produce ATP. [Details of the metabolic pathways of cell respiration are not needed but the substrates and final waste products should be known.]
2.8.U2	ATP from cell respiration is immediately available as a source of energy in the cell.
2.8.U3	Anaerobic cell respiration gives a small yield of ATP from glucose.
2.8.U4	Aerobic cell respiration requires oxygen and gives a large yield of ATP from glucose.
2.8.A1	Use of anaerobic cell respiration in yeasts to produce ethanol and carbon dioxide in baking.
2.8.A2	Lactate production in humans when anaerobic respiration is used to maximize the power of muscle contractions.
2.8.S1	Analysis of results from experiments involving measurement of respiration rates in germinating seeds or invertebrates using a respirometer. [There are many simple respirometers which could be used. Students are expected to know that an alkali is used to absorb CO2, so reductions in volume are due to oxygen use. Temperature should be kept constant to avoid volume changes due to temperature fluctuations.]

[Text in square brackets indicates guidance notes]

Starters

Cell processes and energy
Can you remember the functions of life (these were stated in 1.1 An Introduction to cells)? Discuss which ones required energy.

Respiration and ATP: a high speed intro from Hank.

Presentation and notes

The presentation is designed to help your understanding. The notes outline is intended to be used as a framework for the development of student notes to aid revision.

Vocabulary

Correct use of terminology is a key skill in Biology. It is essential to use key terms correctly when communicating your understanding, particularly in assessments. Use the quizlet flashcards or other tools such as learn, scatter, space race, speller and test to help you master the vocabulary.

Below are the notes for this topic. Alternatively the 2.8 Cell respiration notes - the bottom line template can be used as a note construction template in itself or as a checklist if you are using your own or another template such as the Cornell style template.

Mapping activity

This mapping activity from i-Biology can be used to both develop understanding of biological terminology and as a summary activity to illustrate the linkages that exist between the different components of this sub-topic.

Quick Quiz

Quick quiz Use the BioK Quick Quiz on 2.8 Cell Respiration (as directed) to check your understanding of the topic.

Weblinks

ATP
ATP by the Khan Academy

Cell respiration
Introduction to Cellular Respiration by the Khan Academy

Virtual labs
Cell respiration by LabBench

Resources and lab ideas
Respiration experiments by D G MacKean
Cell Respiration using dataloggers by Vernier

Nature of science

Assessing the ethics of scientific research—the use of invertebrates in respirometer experiments has ethical implications. (4.5) [covered by 2.8.S1]