IB Biology Topic A1.1: Water Key Definitions

The attraction between water molecules and other surfaces, enabling water to cling to them and move against gravity.

Buoyancy is the upward force exerted by a fluid (liquid or gas) on an object immersed in it.

Capillary action refers to the movement of water through narrow spaces, even against gravity.

The attraction between water molecules due to hydrogen bonding.

Electronegativity is an atom's ability to attract electrons in a bond.

The region around a star where conditions are "just right" for liquid water to exist on a planet's surface.

The sum of all chemical reactions occurring in an organism to maintain life, including reactions that break down molecules for energy (catabolism) and reactions that build molecules for growth and repair (anabolism).

The amount of energy required to raise the temperature of 1 gram of a substance by 1°C.

Thermal conductivity is the rate at which heat transfers through a substance.

A measure of a fluid's resistance to flow, determined by the internal friction between its molecules. Higher viscosity indicates a thicker, slower-flowing fluid (e.g., honey), while lower viscosity indicates a thinner, faster-flowing fluid (e.g., water).