Osmosis and Diffusion

Osmosis is specifically.....

• 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

In which case would a cell most likely shrink?

• when placed in a solution containing a high salt concentration
• when placed in a isotonic solution
• when placed in a solution containing a low pH
• when placed in a solution containing distilled water

Active transport requires energy because...

• The cell is moving something against a concentration gradient
• The cell is moving something with a concentration gradient

A student noticed that placing wilted lettuce in a bowl of cool water caused the lettuce to become more crisp and firm. What is the best explanation for his observation?

• Water moved into the lettuce cells by active transport.
• Water moved into the lettuce cells by osmosis.
• Salt moved into the lettuce cells by diffusion.
• Water moved out of the lettuce cells by osmosis.

_______ regulates what enters and leaves a cell.  

• Cell Membrane
• Nucleus
• Mitochondria
• Cytoplasm

Where will the water go?

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

Ideally, your cells should be in a(n) _______ solution

• Hypertonic
• Hypotonic
• Isotonic
• Cola

The cell below is in a _________ solution.

• Hypotonic
• Hypertonic
• Isotonic

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 
  

Active transport requires energy because...

• The cell is moving something against a concentration gradient
• The cell is moving something with a concentration gradient