Passive Transport

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 water and water-soluble substances to enter the cell.

Tags

NGSS.MS-LS1-2

Which part of the cell controls the movement of substances?

• mitochondria

• cell membrane

• chloroplast

• nucleus

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

Tags

NGSS.MS-PS1-4

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)
  

Tags

NGSS.MS-LS1-2

What does “high concentration area” mean?

• Spread out
• Tightly packed together
• Uncrowded
• Spacious

Tags

NGSS.HS-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

Tags

NGSS.HS-PS1-5

The picture below is an example of _________________.

• osmosis
• isotonic
• diffusion
• active transport

Tags

NGSS.MS-LS1-2

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

Passive transport requires no

• concentration gradients
• osmosis
• motion
• energy

Passive transport moves molecules from...

• low concentration to high concentration

• high concentration to low concentration