an environmental factor not associated with the activities of living organisms

Conversion of light energy from the sun into chemical energy.

A combination of two or more substances that are not chemically combined

A measure of the amount of matter in an object

A group of stars that form a pattern in the sky

A subatomic particle that has no charge and that is found in the nucleus of an atom

A series of steps followed to solve problems including collecting data, formulating a hypothesis, testing the hypothesis, and stating conclusions.

A diagram that shows the amount of energy that moves from one feeding level to another in a food web

The experimental factor that is manipulated; the variable whose effect is being studied.

Energy that is stored and held in readiness

The continuous process by which water moves from Earth's surface to the atmosphere and back

The diversity of life forms in an environment.

Earth's outermost layer.