HF&F Alleles

Phenotype

the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment

Genotype

unique sequence of DNA. It is used to refer to the two forms a person has inherited from their mother and father, for a particular gene.

Mutations

can create new alleles in a population

• random and hereditable changes in a gene

Can change allele frequency in a population:

1. GENETIC DRIFT
2. GENE FLOW (caused by migration)
3. NATURAL SELECTION

Genetic Drift

Change in allele frequency due to
random chance

The bottleneck effect

occurs when a large population's size is drastically reduced, such as by a
natural disaster, leading to a random loss of genetic diversity

The founder effect

happens when a small group of individuals breaks off from a larger
population to form a new one, and the allele frequencies in this new, smaller population are
different from the original due to the random selection of founders

Gene Flow

the exchange of genes between two populations

Sources of
evidence for
evolution

1. Fossils
2. Anatomy and embryology
3. Biogeography
4. Molecular biology

Homologous structures:

body parts in different
species that are similar because they were
inherited from a common ancestor, though they
may have different functions in the modern
descendants

Vestigial structures:

structures that appear to be
residual parts from a past ancestor.