Diversity, Classification and Variation- Investigating Variation Flashcards
What is variation?
The differences that exist between individuals
Where can variation be seen?
Between species and within species
What can variation be caused by?
Genetic factors- different species have different genes so variation is caused between species, individuals of the same species will have different alleles of the same gene which causes variation within a species
How else can variation within a species be caused?
By differences in the environment
How is most variation within a species caused?
By a combination of genetic and environmental factors
Why do we only look at a sample rather than the whole population?
It would be time-consuming or impossible to look at the whole population
Why should the sample be random?
So it represents the whole population and is not biased
How can you randomly create a sample?
Divide the area into a grid and use a random number generator to select coordinates
Why is it important to analyse the results statistically?
Ensures that any variation observed isn’t just due to chance
How do you calculate the mean?
Mean= total of all values in data/number of values in data
What can the mean be used for?
To tell if there is variation between samples
What does standard deviation tell you?
How much the values in a single sample vary
What does a large standard deviation mean?
Values in the sample vary a lot
What does a small standard deviation mean?
Data varies little
How can standard deviations be plotted?
On a graph or a chart of mean values using error bars
