Passive Transport

_______ regulates what enters and leaves a cell.  

• Cell Membrane
• Nucleus
• Mitochondria
• Cytoplasm

Osmosis requires energy for transport of water molecules

• True

• False

What is plasmolysis?

• When a plant cell loses water and the cell membrane peels away from the cell wall
• When a plant cell gains water and the cell membrane pushes against the cell wall
• When an animal cell gains too much water and bursts
• When an animal cell loses too much water and shrivels

What is diffusion?

• when molecules move from a low concentration to a high concentration 
• when molecules move from a high concentration to a low concentration.
• no movement 
• molecules move everywhere

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 (where the molecules are more crowded together) to a area of low concentration (where molecules are more spread apart)
  

Osmosis

• diffusion of water molecules through a semi-permeable mebrane from an area of low concentration to an area of high concentration
• the diffusion of particles from an area of high concentration to an area of low concentration
• diffusion of water molecules through a semi-permeable membrane from an area of high concentration to an area of low concentration
• the diffusion of particles from an area of low concentration to an area of high concentration

Osmosis is the movement of _____ across a membrane.

• food
• energy
• oxygen
• water

Equilibrium?

• a large  amount of substance on  side of the cell and a small amount on the other side
• a small  amount of substance on  side of the cell and a large amount on the otherside
• equal amount of substance on either side of the membrane  
• no particles on either side of the a cell membrane

Which way will the water molecules move during osmosis?

• Out of the cell, so the cell shrinks.
• Out of the cell, so the cell swells.
• Into the cell, so the cell shrinks.
• Into the cell, so the cell swells.

Passive Transport

• Does require cell energy

• Does NOT require cell energy