Facilitated Diffusion and Ion Channels

Unit 2: Cell Transport

Target: I can explain the role of cell membranes as a highly selective barrier (passive and active transport).

Lesson/Activity:

·       Cell Transport Notes

·       Cell Transport – Osmosis Practice

Cell membrane (phospholipid bilayer) surrounds the whole cell.

Semi/selectively permeable

Controls the concentration gradient - movement of molecules into and out of the cell!

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​Cell Transport through the Cell Membrane

• Simple diffusion - concentration movement from high to low NO ENERGY and NO ASSISTANCE

• Facilitated diffusion - concentration movement from high to low NO ENERGY but USES ASSISTANCE (PROTEIN CHANNEL)
  

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Passive Transport:

• Osmosis is the diffusion of water through a selectively permeable membrane

• Water moves from HIGH concentration to LOW concentration

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Passive Transport: Osmosis (Water Movement)

• Passive transport = NO ENERGY REQUIRED and High to Low movement

• Active transport = REQUIRES ENERGY (ATP)! and concentration movement LOW to HIGH
  

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Active versus Passive Transport

• Exocytosis = movement exiting the cell

• Endocytosis = movement entering the cell

• REQUIRES ENERGY (ATP)!

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Active Transport: Exocytosis and Endocytosis

Multiple Choice

Which type of cell transport is shown in the image?

• diffusion

• facilitated diffusion

• active transport

• osmosis

Multiple Choice

Which type of cell transport is shown in the image?

• diffusion

• facilitated diffusion

• active transport

• osmosis

Multiple Choice

Which cell transport is shown in the image?

• diffusion

• facilitated diffusion

• active transport

• osmosis

Multiple Choice

Which cell transport is shown in the image?

• diffusion

• facilitated diffusion

• active transport

• osmosis

Match

Match the following concentration movements to each cell transport

• active transport

• diffusion

• facilitated diffusion

• osmosis

• exocytosis

low to high

high to low

high to low

high to low

low to high

• low to high

• high to low

• high to low

• high to low

• low to high

Multiple Choice

A person with swollen gums rinses his mouth with warm salt water, and the swelling decreases. Which of the following has occurred?

• The swollen gums have absorbed the saltwater solution.

• The saltwater solution lowers the temperature of the water in the gums.

• The salt in the solution has moved against the concentration gradient.

• The water in the gums has moved out due to the high concentration of salt in the solution.