B9 - respiration

anaerobic respiration

Respiration in the absence of oxygen. This produces lactic acid.

aerobic respiration

Respiration that requires oxygen

Aerobic word equation

glucose + oxygen --> carbon dioxide + water + energy

Anaerobic word equation

glucose -> lactic acid

Test for carbon dioxide

Turns limewater cloudy

Where does aerobic respiration occur?

mitochondria

Why do organisms need energy?

movement, maintain body temp, chemical reactions to build larger molecules

experiment to show: oxygen is taken up and co2 is released during AR?

- jog on spot for 5 mins
- measure BPM before jogging
- measure BPM after jogging for 5 mins
- find the difference in co2 and o2

what is muscle tissue made from?

protein fibres - they contact and relax to make the muscle move

structure of mitochondria for respiration

mitochondria have lots of folds in their membrane that increases surface area for respiration to take place

The body stores glucose as

glycogen

what happens when you exercise?

- heart and breathing rates increase
- body temp increases
- more oxygen being brought in
- fatigue
- sweating
- arteries supplying blood dilate
- increased amount of co2 removed
- cellular respiration increases to supply muscle cells with more energy
- increase in breath volume
- flow of oxygenated blood to the muscle increases

testing fitness

1. measure resting heart rate and breathing rate
2. the fitter you are the lower it'll be - fitter people have a bigger heart and lung - better supply of blood
3. exercise
4. measure heart rate and breathing rate after exercising

what do plant cells form anaerobically

ethanol and carbon dioxide

anaerobic respiration in yeast cells?

fermentation

Fermentation is used to make?

bread and alcohol

Fermentation equation

glucose → ethanol + carbon dioxide

the heart and breathing rate graph:

- the fitter you are the quicker your heart rate will drop back to normal
- breathing rate increases,in need for more oxygen

what effect increased fitness has on the heart and lungs:

heart- helps because more efficient and pump blood around your body better. This means that the heart pushes out more blood with each beat, allowing it to beat slower and keep your blood pressure under control.
lungs - can help improve lung capacity; the amount of oxygen you take in with each breath.

waste product of glucose molecules

lactic acud

oxygen debt

the amount of oxygen required to convert the lactic acid to glucose

how to get rid of the waste lactic acid?

when the exercise is over, lactic acid has to be converted back to glucose in the liver. the glucose produced may then may be broken down to produce co2 and water. this process needs oxygen.

waste products of aerobic

carbon dioxide and water

cellular respiration

exothermic reaction that occurs continuously in living cells

how to muscle fibres occur?

usually occur in big blocks or groups, which contract to cause movement.

glycogen

can be rapidly converted back to glucose to use during exercise

response to exercise

- muscles start contracting harder and faster
- need more glucose and oxygen for respiration
- produce increased amounts of co2 - needs to be removed for muscles to keep working

Metabolism of an organism

the sum of all reactions that take place in a cell or in the body

metabolic reactions

- conversion of glucose to starch, glycogen and cellulose
- photosynthesis
- respiration
- formation of lipid molecules from glycerol and three fatty acids molecules

role of liver

liver cells grow and regenerate themselves very rapidly. very active organ with many metabolic functions

metabolic functions in the liver:

- detoxifying poisonous substances like ethanol and alcohol
- passing the breakdown products in to the blood so they can be excreted in the urine via the kidneys
- breaking down old work out blood cells and stroring the iron until it's needed to synthesise more blood cells

Where is lactic acid broken down?

liver

lactic acid in the liver

blood flowing through the muscles transports lactic acid to the liver where it's converted back to glucose