Cell Unit List #2 Flashcards
(31 cards)
Definition of semipermeable
Allowing passage of certain, especially small, molecules or ions but acting as a barrier to others. Ex. A cell membrane
Phospholipid bilayer
A two-layer arrangement of phosphate and lipid molecules that make up a cell’s membrane
Explain Osmosis
The process by which water passes through a semipermeable membrane into a solution with higher concentration
What does turgid mean?
To be inflated or swollen
What is a vesicle?
A small sac filled with fluid
What is exocytosis?
The export of matter out of a cell
What is endocytosis?
The import of matter into a cell
What is equilibrium?
The state of balance between opposite forces
What is a hydrophilic molecule?
A molecule that readily accepts and absorbs water
What is a hydrophobic molecule?
A kind of non-polar molecule that prefers other solvents over water
What does the fluid mosaic model illustrate?
The plasma membrane of animal cells
What is passive transport?
The movement of biochemicals and other substances across membranes that does not require any energy
What’s active transport?
The movement of biochemicals and other substances across a membrane moving against the concentration gradient
What is simple diffusion?
When a substance passes through a membrane without the aid of an intermediary
What’s the concentration gradient?
The gradual change in concentration of solutes in a solution
What is a hypotonic solution?
A solution with a lower concentration of solutes
What is an isotonic solution?
A solution with equal osmotic pressure
What’s a hypertonic solution?
A solution with higher concentrations of solutes
What is facilitated diffusion?
A type of passive transport that allows substances to cross membranes with the assistance of special transport proteins
What’s a channel protein?
These are trans-membrane proteins that control voltage gradient across the plasma membrane of cells
What is a carrier protein?
These are proteins involved in the movement of ions, small molecules, or macromolecules across a biological membrane.
What is aquaporin?
These are particles embedded in the cell membrane that regulate the flow of water.
What is the function of ATP?
It is the energy currency of life
What is the function of ADP?
These are important energy transfer molecules in cells
