Diffusion and osmosis Flashcards
(18 cards)
What is diffusion?
Movement of particles from high to low concentration.
How oxygen moves from lungs to blood and how food enters blood from small intestine.
What are the requirements for diffusion?
Needs a partially permeable membrane.
What are the requirements for osmosis?
Needs a partially permeable membrane and involves the transport of solutes.
What is active transport?
Movement of particles that requires energy.
How minerals get into root hair cells and how blood enters blood from small intestine.
What are the requirements for active transport?
Needs a partially permeable membrane and works against the concentration gradient.
What happens to the rate of diffusion as surface area increases?
The larger the surface area, the higher the rate of diffusion.
Surface area maximises space for diffusion.
How does temperature affect diffusion?
As temperature increases, particles gain kinetic energy and move faster, increasing the diffusion rate.
What is the relationship between distance and diffusion?
The shorter the distance, the faster the particles can diffuse.
How does concentration affect diffusion?
The steeper the concentration gradient, the faster the particles diffuse.
What is a solute?
The solid that is dissolving in a solution.
What is a solvent?
The liquid that the solid dissolves in.
What is a solution?
The mixture of solute and solvent.
What is concentration?
How much solute is present in a solution.
What does isotonic mean?
Equal amounts of solute and solvent.
What is osmosis?
The diffusion of water molecules from a low concentration to a high concentration.
What can pass through a partially permeable membrane?
Water molecules are small enough to diffuse through a partially permeable membrane.
What characterizes a dilute solution?
A dilute solution contains more water molecules than a concentrated solution.
What happens when solutions of different concentrations are separated by a partially permeable membrane?
Water moves from the dilute solution to the concentrated solution.
