To provide oxygen to the body, blood flows through the heart in a path formed by the right atrium → right ventricle → lungs → left atrium → left ventricle → body. When blood enters the right side of the heart it is deoxygenated. It enters the left side of the heart oxygenated after traveling to the lungs.

Decomposers (saprotrophs) are organisms such as bacteria and fungi that break down the organic matter in the dead bodies of plants and animals into simple nutrients.

A person's genotype is their genetic makeup and includes both dominant and recessive alleles. Phenotype is how the genes express themselves in physical characteristics.

In the mesosphere, temperature again drops as altitude increases until the coldest point in the Earth's atmosphere, the mesopause, is reached where temperatures fall to −225 °F (−143 °C).

Power is the rate at which work is performed or work per unit time: \(P = {w \over t}\) and is measured in watts (W).