Osmosis And Diffusion Flashcards
Osmosis
The movement of water across a semi permeable membrane from an area of high water concentration to an area of low water concentration
Osmosis is a..
Special type of diffusion that does not require energy
What are passive
Osmosis and diffusion
If pure water separates from salt water, the following occurs
- Water molecules move randomly in both directions
- salt molecules cannot move out so more water moves into the salt solution
- this is the water moving from high concentration water to lower concentration water (osmosis)
Diffusion
The movement of molecules from an area of higher concentration to an areas of lower concentration
Active transport
Movement of molecules from a less crowded to a more crowded area with the use of energy
Permeable
Lets everything in and out
Semi permeable
Lets some things in and out
Impermeable
Lets nothing in and out
2 examples and diffusion in everyday life
Smell of perfume
Food colouring in water
What membranes can pass easily across membranes
Water, oxygen and carbon dioxide
What molecules cannot pass across membranes
Salts sugar and proteins
What does osmosis require
A semipermeable membrane
What do you use in the experiment
Visking tubing
Concentrated sucrose/salt solution
Distilled water
Many sea animals have cytoplasm with similar concentration to
sea water
Function of kidneys
To make sure fluid in our bodies that surrounds our cells have stable concentration
Plants membranes are surrounded by a
Cell wall
Plants membranes are
Fully permeable and allow all substances
Roots absorb water by
Osmosis
Turgor
The pressure of the vacuole and cytoplasm against the cell wall
What gives plants their strenghts
Turgor pressure
What happens when the outside water enters the plant cell
The vacuole becomes bigger and the cytoplasm swells
Turgid
When the cells are fully swelled
What happens when bacteria and fungi are placed in a concentrated solution(sugery/salty)
They loose water by osmosis
What happens to food when u put them in concentrated solutions
Enzyme action stops and prevents them from growing causing the food to shrivel up and die
Examples of food in concentrated solutions
Tinned fruits in sugary solution
What happens if an animal cell is in a solution that is less concentrated thats its cytoplasm
The water from outside the call moves into the cell and may cause it to burst or die
What happens if an animal cell is more concentrated than its cytoplasm
The water may leave the animal cell causing the cell to shrivel up and may die