Unit 2: Section 1 - Variation Flashcards
Define intraspecifc variation
Variation within a species
Define Interspecific Variation
Variation which exists between different species
What is a genotype?
The genotype is made up by the alleles an organism has
What is the phenotype?
The characteristics displayed by an organism
What causes variation in an organisms phenotype within a species? Give examples of each
- Genetic factors, the genes inherited from your parents
- Environmental factors, e.g. Diet, minerals, sunlight, temperature
Explain the example of how overeating is affected by genetic and environmental factors
- Environmental, affected by the diet of the person
- Genetic, some people have an allele which means they have 30% fewer dopamine receptors
Give an example of variation being affected by environmental and genetic factors bar overeating
Antioxidants in berries
Environmental, e.g. Water and ion content in soil, sunlight and genetic factors, alleles from parent plants, affect antioxidant levels in berries
What causes variation between species?
Mainly genetic factors, their different genes
How to make a good sample for testing/analysis? Give 3 ways
- large sample size
- split field into grids and random number generator for plant (or just random number generator for humans)
- analyse the results statistically
What does standard deviation tell you about a sample?
It shiws you the variation in a sample, e.g. Small standard deviation means not much variation
Experiment on different types of manure on plant growth, why was one sample given no manure but otherwise treated the same?
To be a control, to allow comparison
What factors should be taken into consideration when selecting a sample? Give 3 examples
- age
- gender
- ethnic origin
