Unit 2: The Cell

Nucleus: Stores DNA for the cell.

Eukaryotic cell: Has a nucleus.

Prokaryotic cell: No nucleus.

Light microscope: uses lenses for focus.

Electron microscope: Creates beam of electrons for focus. It can be scanning, or transmission.

Cell fractionation: Taking a cell apart to study it.

Organelle: Organ for a cell.

Mitochondrion: A organelle that makes ATP (a kind of chemical energy) for the cell. Has it's own DNA.

Chloroplast: organelle in plant cells. Used for photosynthesis. Has it's own DNA.

Rough endoplasmic reticulum: Organelle in a cell. Has lots of ribosomes on it's surface, so it appears rough when looking at it through a microscope. Creates secretory proteins and membranes.

Smooth endoplasmic reticulum: Organelle in a cell. Does not have ribosomes on it surface, so it appears smooth when looking at it through a microscope. Used for metabolic processes.

Lysosome: Used to hydrolyse macromolecules.

Vesicle: Transporter in the cell.

peroxisomes: Creates toxic hydrogen peroxide away from the rest of the cell. Fortunately it can also turn hydrogen peroxide back into water.

Cytoskeleton: skeleton for the cell. Also used in cell motility when it interacts with motor proteins.

Cell wall: Extracellular structure of plant cells.

Cytoplasm: Area of cell outside the nucleus.

Ribosome: Cellular components that carry out protein synthesis.

Golgi apparatus: Ships and stores products of the endoplasmic reticulum out into the cell.

Cristae: Fold in mitochondria

Nucleolus: Mass of densely stained granules and fibres adjoining part of the chromatin.

Diffusion: Substances move to areas with less concentration of itself.

Concentration gradient: The gradient of the concentration of a substance.

Integral proteins: Penetrate the hydrophobic interior of the lipid bilayer.

Peripheral proteins: Not embedded in the lipid bilayer. loosely bound to the membrane.

Transport protein: Protein in the membrane that moves substances out of the cell.

Osmosis: When water moves down its concentration gradient.

Osmoregulation: When a cell regulates water flowing in and out of itself.

Facilitated diffusion: when a substance is assisted in moving down its concentration gradient.

Active transport: When a substance is moved against its concentration gradient.

Electrochemical gradient: A substance's concentration gradient plus some electrical forces control the movement of the substance.

Cotransport: A transport protein that uses the diffusion of one substance to power the active transport of another.

Exocytosis: The bulk transport of a large molecule from in the cell to out of the cell. A vesicle carries the molecule and then merges with the membrane. Releasing the molecule outside of the cell.

Endocytosis: When a pocket forms in the membrane to capture a substance and bring it back into the ell by turning into a vesicle. There are 3 types of endocytosis.

Phagocytosis: A type of endocytosis. Where a cell "eats" a substance by engulfing it with pseudopodia.

Pinocytosis: A type of endocytosis. Where a cell "drinks" substances by engulfing any substance it can capture.

Receptor mediated endocytosis: A type of endocytosis. Where a cell "drinks" a specific substance by using receptors by the substance, and then engulfing those receptors.