Genetics

a species can gradually change into new species

genes contain the code to make proteins

proteins are made from instructions in genes

Emigration is the act of moving out of a country.

It is distinguished from Immigration that is the act of moving into a new country.

Allele frequency is the frequency (proportion) of alleles in a population. It can be expressed as a percentage or a decimal.

For example, suppose a population has 10 individuals and there are two alleles (A and a) of a gene. Suppose the individuals are as follows:

4 AA individuals = 8 A alleles

4 Aa individuals = 4 A alleles and 4 a alleles

2 aa individuals = 4 a alleles

So there are (8 + 4) = 12 A alleles in the population and (4 + 4) = 8 a alleles in the population.

The frequency of A alleles is therefore 12/20 = 0.6 or 60%.

The frequency of a alleles is 8/20 = 0.4 or 40%.

(Notice that the total number of alleles equals 1.0 or 100%.)

The method an organism uses to produce offspring

the way that a species creates offspring

The birthrate is higher than the death rate (APEX)

Mutations cannot occur - APEX

the population of owls decreases. (Apex)