Independent Variable This is the cause Dependent Variable Th

Independent Variable: This is the cause.

Dependent Variable: This is the response or effect.

One hundred samples of several different plants were placed in each of six sealed containers with water in them. At the end of two days the amount of oxygen produced was measured. Results are shown in the table below.

Container

Plant

Height of Plant

Light Intensity

Source of Light

Distance from Light

mL O₂ Produced

1

Iris

4\"

High

Artificial

6\"

16

2

Iris

4\"

High

Natural

6\"

13

3

Iris

6\"

Low

Artificial

5\"

12

4

Carnation

6\"

High

Natural

4\"

13

5

Carnation

6\"

Low

Natural

4\"

9

6

Carnation

4\"

Low

Artificial

5\"

14

Multiple Choice: Which container had the slowest rate of photosynthesis? (5 points)

a. 1

b. 2

c. 3

d. 4

e. 5

f. 6

Container	Plant	Height of Plant	Light Intensity	Source of Light	Distance from Light	mL O2 Produced
1	Iris	4\"	High	Artificial	6\"	16
2	Iris	4\"	High	Natural	6\"	13
3	Iris	6\"	Low	Artificial	5\"	12
4	Carnation	6\"	High	Natural	4\"	13
5	Carnation	6\"	Low	Natural	4\"	9
6	Carnation	4\"	Low	Artificial	5\"	14

Solution

Multiple Choice: Which container had the slowest rate of photosynthesis? (5 points)

Answer: e. 5

Photosynthesis reaction: carbon dioxide gas + water + energy --> food + oxygen gas. In Container 5, light intensity is low and O₂ produced is 9ml, production of O₂ is very less compared to the other containers. Light intensity is one of the factor that limit the rate of photosynthesis. Hence container 5 has the slowest rate of photosynthesis.

It is assumed that the production of oxygen is proportional to the rate of photosynthesis, so the faster the oxygen production the faster the photosynthesis. If the light intensity increases, the rate of photosynthesis will increase at a proportional rate and more oxygen will be produced resulting an increase in the oxygen levels. Less oxygen will be produced for lower light intensity.