Osmosis - GCSE

Osmosis is the movement of _____ across a membrane.

• food
• energy
• oxygen
• water

Permeable means

• things can pass through
• the concentration levels are different
• it is permanent
• things are stuck

What is the definition of  Selective Permeability?

• The movement of materials across the cell membrane that requires NO ENERGY from the cell.
  
• The movement of materials through (or across) the cell membrane
  
• The ability of the cell membrane to allow some things to pass through while preventing other things from passing through.
• The movement of molecules from an area of high concentration to a area of low concentration 
  

When both inside and outside of a cell have the same amount of water it is said that the cell has reached a state of

• Osmosis
• Diffusion
• Equilibrium

Where will the water go?

• Into the cell
• Out of the cell
• Equally in & out - it's isotonic
• There is no water

During osmosis

• water moves from high water concentration to low water concentration

• large or oddly shaped molecules move across a cell membrane
• water moves when energy is used
• water moves from low water concentration to high water concentration

In the given scenario what will happen?  An egg is placed in pure water for 48 hours.

• The egg will gain water and swell.
• Water will move in and out of the cell equally, and the cell with neither shrink nor swell.
• The egg will lose water and shrink.

What is diffusion?

• when molecules move 
• when particles move from a high concentration to a low.

• no movement 
• molecules move everywhere

Where is there a low concentration of dye?

• at the bottom of cup
• in the color
• at the top of cup 
• no concenteraion gradient

The picture below is an example of _________________.

• osmosis
• isotonic
• diffusion
• active transport