MYP Integrated Sciences Scale and Structure Key Definitions

1 atomic mass unit (1 u) is defined as one-twelfth of the mass of a carbon-12 atom.

It defines which element the atom is by indicating the number of protons in the nucleus.

For a fixed amount of gas at constant temperature, pressure is inversely proportional to volume.

A selectively permeable phospholipid bilayer with embedded proteins that surrounds all cells, controlling the movement of substances in and out of the cell.

A rigid structural layer composed primarily of cellulose (in plants) that surrounds the cell membrane, providing mechanical support and protection.

Charles’s Law describes how the volume of a gas changes with temperature when pressure is constant.

Double-membrane-bound organelles found in plant cells and algae containing chlorophyll, which are the site of photosynthesis.

It describes how much a substance can decrease in volume when external pressure is applied.

The aqueous, gel-like substance enclosed by the cell membrane that contains all organelles, dissolved nutrients, enzymes, and where many metabolic reactions occur.

Density is the amount of mass per unit volume of a substance.

It explains how much matter is packed into a certain volume.

The process by which a cell becomes specialized to perform a specific function, involving changes in structure and which genes are expressed.

The net movement of particles from an area of higher concentration to an area of lower concentration, down a concentration gradient, as a result of random movement.

Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration.

The process in which particles spread from regions of high concentration to regions of low concentration.

For a fixed amount of gas at constant volume, pressure is directly proportional to temperature (in Kelvin).

Atoms of the same element (same protons/atomic number) that have different numbers of neutrons, resulting in different mass numbers

Latent heat is the energy absorbed or released without a change in temperature while a substance changes state.

Energy required to change 1 kg (or 1 mole) of a substance from solid to liquid at constant temperature.

Energy required to change 1 kg (or 1 mole) of a substance from liquid to gas at constant temperature.

The total number of protons and neutrons in the nucleus.

Organelles enclosed by a phospholipid bilayer membrane that creates a separate internal environment from the cytoplasm.

Double-membrane-bound organelles that are the site of aerobic cellular respiration, converting glucose and oxygen into ATP (usable energy).

A temporary copy of a gene used to carry instructions to the ribosome.