bioenergetics

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photosyntheseis:

carbon dioxide + water --> glucose + oxygen
light
chlorophyll

6C02 + 6H2O --> C6H1206 + 602
aerobic: respiration:

glucose + oxygen → carbon dioxide + water + energy released
C6H12O6 + 6O2 → 6CO2 + 6H2O + energy released
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measuring photosynthesis:
the rate of oxygen output
the rate of carbon dioxide uptake
the rate of carbohydrate production
factors affecting photosynthesis:
light intensity
carbon dioxide concentration
temperature
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Light intensity
Without enough light, a plant cannot photosynthesise very quickly - even if there is plenty of water and carbon dioxide and a suitable temperature.

Increasing the light intensity increases the rate of photosynthesis, until some other fact
Carbon dioxide concentration
Carbon dioxide – with water – is one of the reactants in photosynthesis.

If the concentration of carbon dioxide is increased, the rate of photosynthesis will therefore increase.

Again, at some point, a factor may become limi
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emperature
The chemical reactions that combine carbon dioxide and water to produce glucose are controlled by enzymes. As with any other enzyme-controlled reaction, the rate of photosynthesis is affected by temperature.

At low temperatures, the rate of ph
Chlorophyll
Chlorophyll absorbs the light energy required to convert carbon dioxide and water into glucose.

Chlorophyll is green - so absorbs the red and blue parts of the electromagnetic spectrum and reflects the green part of the spectrum.
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The compensation point is the light intensity at which the rate of photosynthesis is equal to the rate of respiration.
Respiration releases energy – it is an exothermic process.
The process of photosynthesis requires energy – it is endothermic.
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anaerobic repsiration:
glucose → lactic acid + energy released


Most organisms cannot respire without oxygen but some organisms and tissues can continue to respire if the oxygen runs out.
Aerobic respiration
Respiration using oxygen to break down food molecules is called aerobic respiration. Glucose is the molecule normally used for respiration – it is the main respiratory substrate. Glucose is oxidised to release its energy.
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Muscles need energy to contract. While exercising, the muscles need additional energy as:

the breathing rate and volume of each breath increases to bring more oxygen into the body and remove the carbon dioxide produced
the heart rate increases, to supply
During long periods of vigorous activity:

lactic acid levels build up
glycogen reserves in the muscles become low as more glucose is used for respiration, and additional glucose is transported from the liver.
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When a period of exercise is over, lactic acid must be removed. The body's tolerance of lactic acid is limited.These processes require oxygen. This is why, when the period of activity is over, a person’s breathing rate and heart rate do not return to norm
Metabolism is the term used for all the chemical reactions that go on inside an organism's body.
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Other cards in this set

Card 2

Front

measuring photosynthesis:
the rate of oxygen output
the rate of carbon dioxide uptake
the rate of carbohydrate production

Back

factors affecting photosynthesis:
light intensity
carbon dioxide concentration
temperature

Card 3

Front

Light intensity
Without enough light, a plant cannot photosynthesise very quickly - even if there is plenty of water and carbon dioxide and a suitable temperature.

Increasing the light intensity increases the rate of photosynthesis, until some other fact

Back

Preview of the front of card 3

Card 4

Front

emperature
The chemical reactions that combine carbon dioxide and water to produce glucose are controlled by enzymes. As with any other enzyme-controlled reaction, the rate of photosynthesis is affected by temperature.

At low temperatures, the rate of ph

Back

Preview of the front of card 4

Card 5

Front

The compensation point is the light intensity at which the rate of photosynthesis is equal to the rate of respiration.

Back

Preview of the front of card 5
View more cards

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