Organisms of the same species at the same level of descent from a common ancestor:

Improvement of a trait or function through natural selection.

A characteristic of an organism:

Organisms inherit two possibilities for each trait, one from each parent. This combination of genes is its:

A process by which organisms with favorable traits produce more successful offspring than organisms with less favorable traits, causing the favorable traits to become more common in the population.

An organisms traits are caused by its genotype. The effect is the organisms:

A group of organisms of the same species that can produce fertile offspring and are in the same area.

How many alleles does an organism inherit from each parent?

Why are siblings similar but not exactly the same?

Traits that are considered helpful for an organisms to survive in its environment are:

Black labs (dominant fur color) can still have yellow puppies (recessive fur color) under what conditions?

How many chromosomes do human gametes have?

What is the percent chance that offspring will inherit a homozygous recessive genotype if both parents are heterozygous for the trait?