Respiration reaction in living organisms

To describe the reaction of respiration including reactants and products

1. Respiration

2. State the uses of energy in the body of humans: muscle contraction, protein synthesis, cell division, active transport, growth, the passage of nerve impulses and the maintenance of a constant body temperature State that respiration involves the action of enzymes in cells USE OF ENERGY IN HUMAN BODY 1

3. Respiration Respiration is a chemical reaction that happens in all our cells to release energy . This can be used for Contraction of muscle cells, producing movement Active transport of molecules and ions Building large molecules , such as proteins Cell division Growth, Passage of nerve impulses The reaction also releases some heat which is used to maintain steady body temperature. Copyright © 2014 Henry Exham

4. Respiration supplies energy for: muscle contraction Germination (growth) cell division chemical changes in cells Some examples of the use of energy in organisms 10 Making proteins Nerve impulses Maintenance of a constant body temp

5. Glucose and oxygen react to produce energy for muscle contraction 4 RESPIRATION 5 Carbon dioxide is carried to the lungs by the blood 15 One example of respiration in ourselves 1 . Air taken in 1 .Food taken in 2 . The lungs absorb oxygen from the air 2 . The stomach and intestine digest food. One of the products is glucose 3 . The blood stream carries glucose and oxygen to the muscles

6. 2 IMPORTANT: 1. ‘RESPIRATION’ IS CENTRAL TO ALL LIVING PROCESSES 2. RESPIRATION INVOLVES THE ACTION OF ENZYMES IN CELLS 3. RESPIRATION =/= BREATHING

7. Define aerobic and anaerobic respiration along with the balanced symbol and word equation for both types of respiration.

8. One example of an energy-producing reaction in cells is the breakdown of sugar when it combines with oxygen This can be represented by the equation C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + energy sugar (glucose) oxygen carbon dioxide water This means that one molecule of sugar reacts with six molecules of oxygen to produce six molecules of carbon dioxide and six molecules of water. Energy is released during this process Aerobic respiration

9. Question 1 What is the most important point about respiration? (a) it uses oxygen (b) It produces energy (c) It produces carbon dioxide (d) It needs food and air 16

10. Question 2 In which part of the human body is respiration most likely to be occurring? (a) The lungs (b) The heart (c) The muscles (d) All of these 17

11. Question 3 Which of these are waste products of respiration? (a) Carbon dioxide (b) Water (c) Oxygen (d) Nitrogen 18

12. Question 4 Which of the following would be reliable indicators of respiration in a living organism? (a) Output of water vapour (H 2 O) (b) Output of carbon dioxide (CO 2 ) (c) Uptake of oxygen (O 2 ) (d) Production of energy 19

13. Question 5 Which of the following statements are correct? (a) We breathe in air (b) We breathe in oxygen (c) We breathe out air (d) We breathe out carbon dioxide 20

14. Answer Correct 21

15. Answer Incorrect 22

16. 23 Anaerobic Respiration

17. Types of respiration During aerobic respiration , a respiratory substrate, e.g. glucose, is split in the presence of oxygen to release carbon dioxide and water. A large number of ATP molecules are produced, releasing the energy from the glucose. C 6 H 12 O 6 + 6 O 2  6 CO 2 + 6 H 2 O + 36 ATP In anaerobic respiration , glucose is converted (in the absence of oxygen) to either lactate or ethanol. The ATP yield is low. C 6 H 12 O 6  2 C 3 H 6 O 3 + 2 ATP lactate C 6 H 12 O 6  2 C 2 H 5 OH + 2 CO 2 + 2 ATP ethanol

18. Anaerobic respiration can be represented by the equation C 6 H 12 O 6 2C 2 H 5 OH + 2CO 2 glucose alcohol energy For example, our own muscles resort to anaerobic respiration when oxygen is not delivered to them fast enough. The energy released by anaerobic respiration is considerably less than the energy from aerobic respiration. Anaerobic respiration takes place at some stage in the cells of most living organisms.

19. Aerobic and anaerobic bacteria Bacteria which need oxygen in order to respire are called aerobic bacteria . Aerobic bacteria are likely to be found in the air, water and soil where oxygen is available Bacteria which can respire without needing oxygen are called anaerobic bacteria Anaerobic bacteria are to be found in situations where oxygen is lacking, such as in stagnant water, waterlogged soils or the intestines of animals 28

20. Fermentation One form of anaerobic respiration in bacteria and yeasts is called fermentation . During fermentation, sugar is broken down to alcohol and carbon dioxide The reaction described in slide 25 is an example of fermentation Fermentation is involved in brewing and wine-making 30

21. Yeasts 0.005mm single yeast cell Yeast cells dividing cell wall nucleus cytoplasm vacuole 29

22. Wine making Grapes are crushed and the sugar they contain is fermented by yeasts to produce alcohol and carbon dioxide. The carbon dioxide usually escapes but if the wine is bottled before fermentation is complete, the carbon dioxide dissolves and escapes as bubble when the bottle is opened This is the case with ‘sparkling’ wines such as Champagne Different varieties of grape produce different types of wine

23. Black grapes growing in a vineyard © Ilan’s Wine Making 32

24. Brewing In brewing beer, a sugary product (malt) is dissolved out of germinating barley Yeast is added to this solution and fermentation begins, producing alcohol and carbon dioxide Some of the carbon dioxide escapes but the rest dissolves in the beer when it is bottled or put into casks When the bottles or casks are opened, the dissolved CO 2 escapes as bubbles 33

25. Beer fermenting ©Stuart Boreham/CEPHAS 34

26. Baking In baking, yeast is added to a mixture of flour and water, made into the form of a dough The yeast first changes the flour starch into sugar and then ferments the sugar into alcohol and CO 2 The CO 2 forms bubbles in the dough which cause it to expand (‘rise’) When the dough is baked, the heat evaporates the alcohol but makes the trapped bubbles expand giving the bread a ‘light’ texture 35

27. 36 The yeast is mixed with the dough After 1 hour in a warm place the dough has risen as a result of the carbon dioxide produced by the yeast Dough Rising

28. The ‘holes’ in the bread are made by the carbon dioxide bubbles. This gives the bread a ‘light’ texture 37

29. The ‘holes’ in the bread are made by the carbon dioxide bubbles. This gives the bread a ‘light’ texture 37

30. Define oxygen debt and outline the process involved in repaying oxygen debt

31. Question 1 Which statements are correct ? Anaerobic respiration is different from aerobic respiration because a it produces CO 2 b it does not need glucose c it does not need oxygen d it produces less energy 38

32. Question 2 In what circumstances do our muscle use anaerobic respiration ? a When insufficient glucose reaches the muscles b When the carbon dioxide level increases c When insufficient oxygen reaches the muscles d When we are asleep 39

33. Question 3 Anaerobic bacteria are most likely to be found a in the middle of a compost heap b in the air c in fast-flowing streams d on the surface of the skin 40

34. Question 4 In which of the following is the production of CO 2 more important than the production of alcohol ? a Brewing beer b Fermenting grape juice c Making bread d Bottling wine 41

35. Answer Incorrect 42

36. Respiratory rate The respiratory rate is the rate at which an organism converts glucose to CO 2 and water. It can be calculated by measuring an organism’s rate of oxygen consumption. Studies on simple animals often use a respirometer . Respirometers measure the change in gas volume in a closed system. Any change is due to the respiratory activity of the study organisms. Potassium hydroxide or soda lime is used to absorb the carbon dioxide produced, meaning any changes in volume are due to oxygen consumption.

37. Respiration experiments This apparatus can be used to investigate how small living organisms respire such as woodlice, maggots or germinating seeds. Hydrogencarbonate indicator – This will change colour from red to yellow when the carbon dioxide level increases due to respiration. Gauze Living organisms Copyright © 2014 Henry Exham

38. Respiration experiments Boiled seeds Germinating seeds Cotton wool Thermometer Thermal flask The germinating seeds are respiring and therefore releasing heat. The boiled seeds have been killed and are therefore not respiring anymore. Thermal flask