All Flashcards
What is the effect of increased unsaturated fatty acids on membrane fluidity?
Increases membrane fluidity due to kinks preventing tight packing.
What happens if a cell is placed in a hypertonic solution?
Water moves out of the cell, causing it to shrink.
What happens if a cell is placed in a hypotonic solution?
Water moves into the cell, causing it to swell or burst.
What is the effect of cholesterol on membrane fluidity?
Helps maintain membrane fluidity by preventing it from becoming too rigid or too fluid.
What happens when a receptor protein binds to its signaling molecule?
Initiates a cellular response.
What is the effect of the hydrophobic tails of the phospholipid bilayer on polar molecules?
They repel charged and polar molecules, hindering their passage across the membrane.
Define phospholipid bilayer.
A two-layered arrangement of phospholipids that form a cell membrane, with hydrophobic tails facing inward and hydrophilic heads facing outward.
What is a glycoprotein?
A protein with a carbohydrate attached, involved in cell signaling and attachment.
Define glycolipid.
A lipid with a carbohydrate attached, involved in cell signaling and attachment.
What is the fluid mosaic model?
A model describing the cell membrane as a flexible structure with a mosaic of proteins embedded within the phospholipid bilayer.
Define selective permeability.
The property of a membrane that allows some substances to cross more easily than others.
What are adhesion proteins?
Membrane proteins that form junctions between cells.
What are receptor proteins?
Membrane proteins that receive and bind to signaling molecules, initiating a cellular response.
Compare hydrophilic and hydrophobic regions in the membrane.
Hydrophilic: Attracted to water, located on the exterior | Hydrophobic: Repelled by water, located on the interior
Differentiate between integral and peripheral membrane proteins.
Integral: Embedded within the lipid bilayer | Peripheral: Associated with the membrane surface
Compare channel proteins and transport proteins.
Channel proteins: Facilitate passive transport through channels | Transport proteins: Actively transport substances, often using ATP
Compare glycoproteins and glycolipids.
Glycoproteins: Proteins with attached carbohydrates | Glycolipids: Lipids with attached carbohydrates
Compare the movement of polar vs. nonpolar molecules across the membrane.
Polar: Require transport proteins | Nonpolar: Pass freely