1. 2.8: Cell respiration
Define respiration: controlled release of energy from organic molecules to produce ATP

2. Recap: structure of ATP
A unit of energy (think of it like cellular currency) it is a coenzyme (cannot catalyse reactions alone, works in conjunction with other molecules)
ribose
guanine
inorganic phosphate
deoxyribose
thymine
organic phosphate
nicotinamide
cytosine
adenine
flavine

3. ATP is a source of energy
Energy is released when ATP spits and forms ADP. The energy from this split is immediately available.
A lot of the energy produced by cells ends up as heat (environment) therefore the body needs a continual source of energy.
Cell respiration
ATP
ADP
Cell processes (active)

4. Recap: where in the cell?
Glycolysis
Phosphorylation
Oxidation
Link reaction
Krebs cycle
Oxidative phosphorylation
SL you do not have to know any of the detail of these stages, they just ‘happen’!

5. Types of Respiration Anaerobic Aerobic No oxygen Small yield of ATP
Emergency supply of energy
Oxygen
Large yield of ATP
‘normal’ energy supply

6. Anaerobic respiration
glucose
pyruvate
Animals
Yeast & plants
carbon dioxide + ethanal
lactic acid
ethanol

7. Aerobic respiration Waste products are Carbon dioxide + water glucose
pyruvate
Link reaction
Glucose + oxygen  Carbon dioxide + water
Krebs cycle

8. Background information & procedure on moodle.
Investigation: Investigate how the type of sugar affects the rate of respiration.
Background information & procedure on moodle.
For each type of sugar, record the % CO2 every 60 seconds for 10 minutes. You will need this data to complete this IB HL skill (8.1)
SKILL: Calculate and plot rates of reaction from raw experimental results
If we can source some mealworms before Thursday we could do the respirometer experiment then… any ideas?

9. Homework
Graph the results
Considering these results:
Does yeast use all these sugars equally?
Suggest a reason why.
3. Explain the three most important evaluation points from this experiment.
4. If you were to do this experiment again, what would you change in the procedure?