HISTO LEC: Module 1 - Part IV (Additional info)

DO NOT EXPLOIT.

Simple diffusion

Unassisted net movement of small, nonpolar substances down their concentration gradient across a selectively permeable membrane.

Facilitated diffusion

Movement of ions and small, polar molecules down their concentration gradient; assisted across a selectively permeable membrane by a transport protein.

Channel-mediated

Movement of ion down its concentration gradient through a protein channel.

Carrier-mediated

Movement of small, polar molecule down its concentration gradient by a carrier protein.

Osmosis

Diffusion of water across a selectively permeable membrane; direction is determined by relative solute concentrations; continues until equilibrium is reached.

Active transport

Transport of ions or small molecules across the membrane against a concentration gradient by transmembrane protein pumps.

Vesicular transport

Vesicle formed or lost as material is brought into a cell or released from a cell.

McArdle syndrome and Gaucher

Examples of lysosomal storage diseases caused by defective lysosomal enzymes are Hurler syndrome (MPS I), _______, Tay-Sachs, ________, I-cell disease.

Flagellum

Long, singular membrane extension supported by microtubules; present on sperm cell.

Cilia

Short, numerous membrane extensions supported by microtubules, which occur on exposed membrane surfaces of some cells.

Nuclear pores

Allow passage of materials between the cytoplasm and nucleoplasm, including ribonucleic acid (RNA), protein, ions, and small water-soluble molecules.

Cytosol

Provides support for organelles; serves as the viscous fluid medium through which diffusion occurs.

Peroxisomes

Detoxify specific harmful substances either produced by the cell or taken into the cell; engage in beta oxidation of fatty acids to acetyl CoA.

Proteasomes

Degrade and digest damaged or unneeded proteins; ensure quality of exported proteins.

Microfilaments

Maintain cell shape; support microvilli; separate two cells during cytokinesis (a process of cell division); facilitate change in cell shape; participate in muscle contraction.

Nucleolus

A generally spherical, highly basophilic subdomain of nuclei in cells actively engaged in protein synthesis.

Apoptosis

• The process by which redundant or defective cells are rapidly eliminated in a manner that does not provoke a local inflammatory reaction in the tissue.

• Occurs rapidly, with little or no release of proteins that would trigger inflammation, unlike the death of injured cells by necrosis that typically induces local inflammation.