photosynthesis

What is photosynthesis

The endothermic reaction in which energy is transferred from the environment to the chloroplasts by light

The process by which plants make glucose from sunlight

Equation for photosynthesis

Carbon dioxide + water—> glucose +oxygen

balanced symbol of photosynthesis

6CO2+6H2O—»C6H12O6+ 6O2

What absorbs light energy in plants

Chlorophyll- green pigment in chloroplasts

5 factors affecting rate of photosynthesis

Light intensity

Temperature

Water availability

Amount of chlorophyll

Carbon dioxide concentration

How does the factor temperature effect rate of photosynthesis

With an increase an temperature, the rate of photosynthesis increases. As the reaction is controlled by enzymes, this trend continues up to a certain temperature until the enzymes begin to denature and the rate of reaction decreases

How does the factor light intensity effect rate of photosynthesis

For most plants the higher the light intensity the faster the rate of the reaction

How does the factor carbon dioxide concentration effect rate of photosynthesis

Carbon dioxide is also needed to make glucose. As the concentration of carbon dioxide increases, the rate of reaction increases

How does the amount of chlorophyll affect the rate of photosynthesis

Chlorophyll is a pigment in the leaf that converts light energy to food for the plant, and therefore is essential. The higher the amount of chlorophyll, the greater rate of photosynthesis

5 uses of glucose from photosynthesis

Respiration

Converted into insoluble starch for storage (in stems)

Produce fat or oil for storage (in seeds)

To produce cellulose to strengthen cell walls

Combined with nitrates to form amino acids which produce proteins

What are the sugars produced in photosynthesis used for

Make all the substances a plant needs and used in respiration

Adaptions of leaves for photosynthesis

Large surface area to absorb more light

Thin so short diffusion pathway for gases

Chlorophyll to absorb light energy

Air spaces allow carbon dioxide and oxygen to diffuse easily

Stomata allow gas exchange

Xylem brings water and phloem carries glucose away

What is a limiting factor

Soemthing that stops the rate increasing

Only one factor limits the rate at a time

Once it is no longer limiting another factor becomes limiting

Storage of glucose

Glucose in insoluble and reactive

Concerted to starch for storage

Stored in roots, stems and seeds