Slides in this set

Slide 1

Preview of page 1

Biology Unit 2 Revision Notes…read more

Slide 2

Preview of page 2

Variation: Key Words
· Interspecific- among different species
· Intraspecific- within the same species
· Continuous ­ data that continues ( height in
· Discrete- groups that do not overlap
· Mean ­ sum of the numbers/ the participants
· Median ­ the middle number
· Standard Deviation- how far away from the mean
are they?…read more

Slide 3

Preview of page 3

Variation: Types of
Discrete ( Discontinuous) Continuous
· Variation that has clear cut categories · Polygenic. Several genes affect the
· Depends on one or a few genes same characteristic
(monogenic) · Can be more strongly affected by the
· Limited number of possible environment
phenotypes · Due to number of genes and
· Isn't strongly influenced by the environmental influences there's lots
environment of possible phenotypes
Genotype- The make up of an individuals genes and varying combinations of alleles
Phenotype ­ the outward expression of varying alleles these are the characteristics of
an individual…read more

Slide 4

Preview of page 4

Variation: Investigations
Investigating Variation
· Avoid bias by using a large sample size/
random sampling
· If the data is continuous use a line graph
· If the data is discontinuous use a frequency
historgram…read more

Slide 5

Preview of page 5

Variation: Genetic Diversity
· Genetic diversity is due to the different
combinations of genes and the way in which
they are expressed
· Recessive alleles require both pairs in the
homozygous recessive to be expressed
· Triplet bases code for an amino acid the
sequence of amino acids code for a protein
· Genome is the sequence of all the bases…read more

Slide 6

Preview of page 6

· The more diverse the species the larger the gene
· Artificial breeding- we choose favourable
characteristics which we wish to breed
· Genetic diversity exists within the same species
· The closer the relation between 2 different
species, the more DNA they will share.
· Variation is cause by: Crossing Over, Independent
assortment, mutations, and recombination of
parental chromosomes in the zygote…read more

Slide 7

Preview of page 7
Preview of page 7

Slide 8

Preview of page 8
Preview of page 8

Slide 9

Preview of page 9
Preview of page 9

Slide 10

Preview of page 10
Preview of page 10


No comments have yet been made

Similar Biology resources:

See all Biology resources »