The Earth's rocks fall into three categories based on how they're formed. Igneous rock (granite, basalt, obsidian) is formed from the hardening of molten rock (lava), sedimentary rock (shale, sandstone, coal) is formed by the gradual despositing and cementing of rock and other debris, and metamorphic rock (marble, slate, quartzite) which is formed when existing rock is altered though pressure, temperature, or chemical processes.

Both are part of the peripheral nervous system. The somatic nervous system sends sensory information to the central nervous system and controls voluntary actions while the autonomic nervous system regulates involuntary activity in the heart, stomach, and intestines.

Cell division is the process by which cells replicate genetic material in the nucleus and consists of several phases, beginning with interphase and ending with cytokinesis.

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.

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