Field Investigations
Q1.
Some students investigated the size of a population of dandelion plants in a field.
The diagram below shows the field.
 
The students:
•   placed a 1 m × 1 m square quadrat at 10 random positions in the field
•   counted the number of dandelion plants in each quadrat.
The table below shows the students’ results.
 
Quadrat number	Number of dandelion plants	
1	6	
2	9	
3	5	
4	8	
5	0	
6	10	
7	2	
8	1	
9	8	
10	11	
(a)  Why did the students place the quadrats at random positions?
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(1)
(b)  Estimate the total number of dandelion plants in the field.
Calculate your answer using information from the diagram and the table above.
Give your answer in standard form.
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Total number of dandelion plants = ____________________
(5)
Quadrats 5, 7 and 8 were each placed less than 10 metres from the woodland.
These quadrats contained low numbers of dandelion plants.
The students made the hypothesis:
‘Light intensity affects the number of dandelion plants that grow in an area.’
(c)  Plan an investigation to test this hypothesis.
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(6)
(d)  Light is an environmental factor that affects the growth of dandelion plants.
Give two other environmental factors that affect the growth of dandelion plants.
1. _________________________________________________________________
2. _________________________________________________________________
(2)
(Total 14 marks)