Respiration

Page
3

pyruvic acid

carbon dioxide + water

Slide 28

ATP production – summary

36 ADP + 36 Pi =

36 ATP

glucose

pyruvic acid

carbon dioxide + water

2 ADP + 2 Pi =

2 ATP

Slide 29

Summary of ATP production

Stage 1 and 2 release all the chemical energy in one molecule of glucose to make a total of 38 ATP molecules.

2 molecules ATP from glucose  pyruvic acid

36 molecules ATP from pyruvic acid  carbon- dioxide + water

Total 38 molecules ATP

Slide 30

Anaerobic Respiration (in animals)

anaerobic = in the absence of oxygen

Slide 31

In low oxygen conditions or during heavy exercise, when not enough oxygen can be supplied, muscle cells swap to anaerobic respiration

Slide 32

glycolysis still happens as it does not require oxygen

in absence of oxygen pyruvic acid is turned into lactic acid.

pyruvic acid

lactic acid

glucose

2 ADP + 2 Pi

2 ATP

Slide 33

A build up of lactic acid produces muscle fatigue. Muscle fatigue makes muscles ache and contract less powerfully. A recovery period is needed. During this time more oxygen is taken in to convert the lactic acid back into pyruvic acid again. The volume of oxygen needed is called the oxygen debt.

Slide 34

Summary

oxygen debt

e.g. during hard exercise

oxygen debt

repaid during recovery time

glucose

pyruvic acid

lactic acid

Slide 35

Anaerobic Respiration in plants

The same process occurs in plants and yeast in low oxygen conditions, e.g. muddy, flooded soils.

Slide 36

glycolysis still happens, producing

2 ATP molecules

This time in absence of oxygen, pyruvic acid is turned into carbon dioxide and ethanol

glucose

pyruvic acid

ethanol + carbon dioxide

This is irreversible

2 ADP + 2 Pi

2 ATP

Slide 37

Comparison of aerobic and anaerobic respiration

Slide 38

Task

Prepare a series of PowerPoint slides which show the importance of anaerobic respiration in the brewing and bread-making processes.