Investigating Whether Light Intensity Affects Photosynthesis

Investigating Whether Light Intensity Affects Photosynthesis

Background Information:

Photosynthesis means “making through light” and occurs in the cells of

green plants, which are exposed to light.

The word equation for photosynthesis is:

Light

[IMAGE]Carbon Dioxide + Water Glucose + Oxygen

Chlorophyll

Although most of the glucose produced is converted into insoluble

starch for storage in the stem, leaves or roots, some is used

immediately by the plant to provide via respiration.

There are three things which limit the rate of photosynthesis, which

are temperature, carbon dioxide concentration and light intensity.

This is shown as when the temperature, carbon dioxide concentration

and light intensity increases, so does the rate of photosynthesis.

Prediction:

I think that at high light intensity the rate of photosynthesis will

increase because, as shown in my background information, as light

intensity increases, so does the rate of photosynthesis. I also think

at low light intensity the rate of photosynthesis will decrease. I

think this because, as proven in my background information, light is

needed for photosynthesis and means “making through light”.

Above is a graph to show what I predict my results will show about the

rate of photosynthesis as the light intensity increases. I think as

the light intensity increases the rate of photosynthesis will increase

because, as shown in my background information light is need to

photosynthesize.

I think eventually the graph will level out because the light

intensity will not be bale to increase anymore.

Preliminary work:

Below is a table showing our results after completing our preliminary

test.

Distance the light is from beaker (cm)

Bubble produced per minute

25

6

20

13

15

17

10

19

5

21

0

23

Using these results I can work out what I am going to use. Below is a

list: