Transport processes Flashcards
What is diffusion?
Diffusion is the spreading out of particles of any substance in solution, or particles in a gas, resulting in the net (overall) movement of particles from an area of an higher concentration to an area of lower concentration.
Which way does Diffusion take place?
Diffusion takes place down a concentration gradient.
What surface does diffusion take place through?
Diffusion may take place across a semi-permeable membrane of a cell.
What Factors affect diffusion?
Temperature
When does Diffusion stop?
When both sides are at a equilibrium.
What is osmosis?
Osmosis is the movement of water molecules across a partially permeable membrane from a region of high water concentration to a region of low water concentration.
What does passive mean?
Passive means it does not need energy.
What is active transport?
Active transport is the movement of particles against a concentration gradient using energy released during respiration.
Give an example of Exchange surfaces?
- Gills on a fish
- Trachea
- Spiracles
What are the main features of Exchange surfaces?
- Large surface area to volume Ratio
- Moist surface for efficient transfer
- Close proximity to blood vessels
What are the three Factors that affect diffusion?
- Concentration gradient
- temperature
- membrane surface area
