Biological Membranes

Front 1

Glycoprotein Coat

Back 1

Created by carbohydrates associated with membrane-bound proteins.

Front 2

Phospholipids in Membrane

Back 2

Move rapidly in plane of membrane through simple diffusion.

Front 3

Lipid Rafts

Back 3

Small collections of similar lipids with or without associated proteins that serve as attachment points for other biomolecules. Serve a role in signaling.

Front 4

Flippases

Back 4

Assist in the transition or flip of lipids between layers.

Front 5

Micelles

Back 5

Monolayered vesicles

Front 6

Liposomes

Back 6

Bilayered vesicles

Front 7

Transmembrane Proteins

Back 7

Proteins that pass completely through the lipid bilayer.

Front 8

Embedded Proteins

Back 8

Proteins that are associated with only the interior or exterior surface of the cell membrane.

Front 9

Membrane-Associated (Peripheral) Proteins

Back 9

Proteins bound through electrostatic interactions with the bilayer, such as rafts, or to other transmembrane/embedded proteins. Includes transporters, channels, and receptors.

Front 10

Cell Adhesion Molecules (CAMs)

Back 10

Proteins that allow cells to recognize each other and contribute to proper cell differentiation and development.

Front 11

Gap Junctions/Connexons

Back 11

Allow for direct cell-cell communication. Formed by alignment and interaction of pores composed of six molecules of connexin, making a spiral pie door.

Front 12

Tight Junctions

Back 12

Prevent solutes from leaking into intercellular space via the paracellular route. Found in epithelial cells, and function as physical links between tissue.

Front 13

Desmosomes

Back 13

Bind adjacent cells by anchoring to their cytoskeletons. Formed by interactions between transmembrane proteins associated with intermediate filaments inside adjacent cells. Found in interface between epithelial tissues. Hemi form attaches epithelial cells to underlying membranes.

Front 14

Simple Diffusion

Back 14

Passive transport where substrates simply move down their concentration gradient directly across membrane. Only barrier is those particles able to cross such a membrane.

Front 15

Osmosis

Back 15

Specific kind of passive transport concerning water, based on concentration. Hypotonic when concentration of solutes inside cell is higher than surroundings, and hypertonic when vice versa.

Front 16

Osmotic Pressure

Back 16

A colligative property (dependent on concentration of dissolved particles but not chemical identity). Uppercase pi = iMRT, where pi equals pressure, i equals van't Hoff factor (number of particles obtained from a single molecule when put in solution), M equals molarity, R equals ideal gas constant, T equals temperature in Kelvins.

Front 17

Facilitated Diffusion

Back 17

Type of passive transport where molecules impermeable to a membrane require an integral membrane protein to serve as a transporter. Carriers are only open to one side (revolving door), channels have an open or closed conformation and are exposed to both sides (like a tunnel).

Front 18

Primary Active Transport

Back 18

Type of active transport that uses ATP or another energy molecule to transport molecules across membrane, typically with the use of a transmembrane ATPase.

Front 19

Secondary Active/Coupled Transport

Back 19

Active transport that uses energy molecules to transport molecules, but does not involve direct coupling to said molecule. Harnesses energy of another particle going down electrochemical gradient to power it's symport/antiport funnel.

Front 20

Pinocytosis

Back 20

Type of endocytosis where fluids and dissolved particles are engulfed by cell.

Front 21

Phagocytosis

Back 21

Type of endocytosis where large solids are ingested by cell.

Front 22

Membrane Potential (Vm)

Back 22

Use Nernst equation to calculate membrane potential from intra/extracellular concentrations of ions, where R is ideal gas constant, T is temperature, z is charge of ion, F is Faraday constant.