3.1 - Components and Structure Flashcards
Glycoproteins
Proteins modified with carbohydrates, often attached to lipids (glycolipids), facing the outside of the cell to form the glycocalix.
Integral Proteins
Proteins that go through the lipid bilayer, performing functions like catalyzing reactions, transporting molecules, and serving as receptors.
Phospholipids
Molecules with hydrophilic phosphate head groups facing the aqueous environment and hydrophobic lipid tails facing each other.
Cell Membrane Composition
Composed of phospholipid bilayer, proteins, glycolipids, and cholesterol.
Cholesterol
Lipid found in cell membranes
Cholesterol in phospholipids
Cholesterol decreases fluidity at high temperatures and increases fluidity at low temperatures.
Degree of Unsaturation in phospholipids
Unsaturated fatty acids increase fluidity by creating space between phospholipids.
Factors affecting membrane fluidity:
-Temperature
-Tail Length
-Degree of Unsaturation
-Cholesterol
Fluid Mosaic
Term describing the cell membrane composed of various molecules that constantly shuffle.
Membrane Protein Functions
Catalyzing reactions, transporting molecules, signaling, anchoring internal structures, cell-cell adhesion, and cell identification markers.
Peripheral Proteins
Proteins located on the outer edges of the lipid bilayer, associated with integral proteins or phospholipids, and involved in various functions.
Phospholipid Mobility
Phospholipids can (1) move laterally, (2) rotate, (3) flex fatty acid chains, and (4) flip-flop via flipases.
Phospholipid Quantity
More phospholipids mean less mobility and lower membrane permeability.
Plasma Membrane
Fluid and constantly rearranging barrier between the inside and outside of the cell.
Tail Length In phospholipids
Longer fatty acid tails decrease fluidity due to more intermolecular interactions.
