What is Photosynthesis?
Photosynthesis is how plants get their food. The reason
why plants have leaves, roots or being green is all linked
to photosynthesis. In photosynthesis, a plant takes
carbon dioxide from the air and water from the soil and
uses the light from sunlight to turn them into food.
Photosynthesis occurs only in the presence of light, and
takes place in the chloroplasts of green plant cells.
Photosynthesis can be defined as the production of
simple sugars (glucose) from carbon dioxide and water
causing the release of sugar and oxygen.
Oxygen is also produced in photosynthesis, plants don't
really need oxygen so they give it out as a waste product
but saves a little bit to use for respiration. The sunlight
is absorbed by a green pigment called chlorophyll.
Most of the glucose is turned into a substance called starch.
Word equation for photosynthesis:
Light energy
Carbon dioxide + Water Glucose + Oxygen
Chlorophyll
Word equation for photosynthesis:
Light energy
6CO + 6H O C H O + 6O
2 2 Chlorophyll 12 6 2
My aim:
My aim is to determine the effect of light intensity on the rate of photosynthesis. To accomplish this I will have to control the amount of water, carbon dioxide and light. Also the distance of the light will have to be controlled by undertaking this there should be different levels of oxygen escaping the plant. The plant will be soaked into water so the oxygen can be measured easily. The oxygen will be measured by the amount of bubbles produced from the plant for a certain amount of time.
Investigate the factors of - Independent variable - I am changing the light intensity.
- Dependent variable - I am measuring the rate of photosynthesis.
- Controlled variable - I am going to keep the level of carbon dioxide the same.
Preliminary experiment
Before doing my actual experiment I have decided to do a