Chapter 1 Flashcards
What does the cell membrane do?
Keeps the concentration of substances fairly constant, and fairly different from the external environment.
What is a fluid mosaic phospholipid bilayer model?
Cholesterol strengthens cell membranes.
Membranes are fluid, can break apart and join back together
What is hydrophobic?
Avoids water
What is hydrophilic?
Interacts with and dissolves in water
What is passive movement?
The movement of molecules which doesn’t require energy.
What is diffusion?
The movement of uncharged particles from high concentration to low.
What is concentration gradient?
The difference between high and low concentration.
What is osmosis?
Osmosis is the diffusion across the cell membrane for water.
What is isotonic?
Two fluids of equal concentration
What is hypotonic?
Solution with low concentration compared to another
What is hypertonic?
Solution with higher concentration compared to another
What is facilitated diffusion?
The movement of charged particles through transport proteins. Two involved are carrier and channel proteins which bind to specific molecules.
What are membrane proteins?
Channel proteins allow for certain particles to enter the cell
What is active transport?
This is the movement of molecules requiring energy which if facilitated by carrier proteins.
What is Endocytosis?
When a particle is to big to diffuse through the membrane, the membrane wraps around it and carries it through the cell.
