Unit B5 notes

Seite 1

TEST FOR STARCH

Safety precautions needed: To prevent ethanol from getting in your eyes you should wear safety glasses, ethanol is highly flammable so it cannot be near a naked flame.

Steps: First the chlorophyll needs to be removed because it acts as a waterproof layer

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PHOTOSYNTHESIS

Photosynthesis takes place in the chloroplasts of plants. During this reaction, a pigment called chlorophyll traps light energy from the sun. This light energy is converted to chemical energy in the form of glucose.

Glucose can then be used for: - Respiration to release energy.

- Stored later for starch.

- Structural compounds like cellulose which forms the cell wall.

This is the equation: 6CO2 + 6H2O -> C6H12O6 + 6O2

Seite 3

ENZYMES

Enzymes are biological catalysts, which means they speed up chemical reactions.

They are specific to one particular substrate because their active site is complementary to the substrate.

Enzymes are not used up in the reactions they catalyse.

Their activity is affected by factors such as temperature and PH.

The reaction depends on the enzyme and substrate colliding