Investigating Variation

Question 1

Causes of variation

Answer 1

Variation can be caused by genetic factors
Different species have different genes
Different organisms of the same species have the same genes but different alleles

And differences in the environment

Most variation in a species is caused by a combination of them both

Question 2

Why random sampling is good

Answer 2

Non biased

Accurate representation

Question 3

What is mean and the formula

Answer 3

The average values collected

Mean
Total of all the values in the date
Divided by
The number of values in your data

Question 4

What is standard deviation

Answer 4

Tells you how much the values in a single sample vary

It’s a measure of the spread of values about the mean

Question 5

Standard deviation formula symbol meanings

Answer 5

S
Standard deviation

Sigma
Sum of

N
The number of values

X
A value in the data set

X with the line on top
Is the mean