Cell Membrane Flashcards
What is the primary function of the cell membrane?
To protect the cell and regulate what enters and exits.
True or False: The cell membrane is impermeable to all substances.
False.
What is diffusion?
The movement of molecules from an area of high concentration to an area of low concentration.
Fill in the blank: The process by which water diffuses across a selectively permeable membrane is called __________.
osmosis.
What are the two main types of diffusion?
Simple diffusion and facilitated diffusion.
Multiple choice: Which type of diffusion requires a transport protein?
Facilitated diffusion.
What is the role of cholesterol in the cell membrane?
To maintain membrane fluidity and stability.
True or False: Active transport requires energy.
True.
What is the difference between passive and active transport?
Passive transport does not require energy, while active transport does.
Short answer: Name one type of active transport.
Sodium-potassium pump.
Fill in the blank: The movement of ions against their concentration gradient is an example of __________.
active transport.
What is a concentration gradient?
A difference in the concentration of a substance across a space.
Multiple choice: Which process is used for the bulk transport of materials into the cell?
Endocytosis.
True or False: Exocytosis is the process of moving materials out of the cell.
True.
What is the function of membrane proteins?
To facilitate transport and communication across the membrane.
Fill in the blank: __________ is the process by which cells release large amounts of materials.
Exocytosis.
Short answer: What is meant by selective permeability?
The ability of the membrane to allow certain substances to pass while blocking others.
What type of molecules can easily pass through the lipid bilayer?
Small nonpolar molecules.
True or False: Facilitated diffusion requires ATP.
False.
Multiple choice: Which type of diffusion occurs through protein channels?
Facilitated diffusion.
What is the role of aquaporins in the cell membrane?
To facilitate the transport of water.
Fill in the blank: The __________ model describes the structure of the cell membrane.
fluid mosaic.
Short answer: Define osmosis.
The diffusion of water across a selectively permeable membrane.
What is the effect of a hypertonic solution on a cell?
It causes the cell to shrink due to water loss.
