Wednesday, October 8, 2008

Vocab

Organelle: Part of a cell with a specific function

Plasma membrance: Thin outer boundary of a cell that regulates the traffic of chemicals between the cell and its surroundings
Nucleus: In an atom, the central core that contains protons and neutrons.

Cytoplasm: Region of a cell between the nucleus and the plasma membrane.

Cell wall: Strong wall outside a plant cell's plasma membrance that protects the cell and maintains its shape.

Prokaryotic cell: Cell lackinga nucleus and most other organelles.

Eukaryotic cell: Cell with a nucleus and other internal organelles.

Diffusion: Net movement of the particles of a substance from where they are more concentrate to where they are less concentrated.e

Equilibrium: Point at which the number of diffusing molecules moving in one direction is equal to the number moving in the opposite direction.

Selectively permeable membrane: Membrane that allows some substances to pass more easily than others and blocks the passage of some substances altogether.