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)
  

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

Tags

NGSS.MS-PS1-5

Where is there a low concentration of dye?

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

Passive transport requires no

• concentration gradients
• osmosis
• motion
• energy

Diffusion & Facilitated Diffusion are both __________ transport.

• Passive

• Active

• Easy

• Free

What is the movement of particles with the concentration gradient using protein channels?

• diffusion

• facilitated diffusion

• active transport

• enzymatic reactions

Phospholipids have a -

• nonpolar head and a nonpolar tail.

• polar head and a polar tail.

• nonpolar head and a polar tail.

• polar head and a nonpolar tail.

Diffusion moves along the __________

• concentration gradient

• Avogadro's constant

• conservation of energy

Tags

NGSS.HS-PS1-5

Cell membranes are described as selectively permeable.

Four students were asked to explain what this means. Which one is correct?

• Student 1: Cell membranes prevent all materials from entering the cell.

• Student 2: Cell membranes only provide structural support for the cell.

• Student 3: Cell membranes regulate which substances can enter and exit the cell.

• Student 4: Cell membranes allow all substances to enter the cell.

Tags

NGSS.MS-LS1-2