Aim #9: How can we compare active and passive transport?

Cell Transport ABSORB DISTRIBUTE

The Cell Living cell Non-living cell surroundings Secrete chemicals (hormones, neurotransmitters, enzymes, antibodies…) Secrete Metabolic wastes (CO 2, urea) Take in: O 2, end products of digestion, minerals, chemical messengers (hormones & neurotransmitters)

Do all things get through the cell membrane? SELECTIVELY PERMEABLE Water Molecules

Explain how this picture illustrates a concentration gradient?

How does a rollercoaster work?

When will he need energy? Should I go against the gradient or down the gradient

5) What are the two types of transport? ACTIVE TRANSPORT PASSIVE TRANSPORT

Active Transport A.Energy required B.Against concentration gradient C.From low to high

Passive Transport A.No energy required B.“Down” the concentration gradient C.From high to low

6) Three types of passive transport: a) Diffusion- movement of O 2 and CO 2 What direction would the materials move in?

b) Facilitated Diffusion- use transport proteins (channels) to move materials from an area of high concentration to low concentration Alcohols and glucose

c) Osmosis- diffusion of water

*How does concentration gradient affect diffusion?

7) Examples of Active Transport? a)Contractile vacuole- used to pump out water from freshwater organisms like paramecium

b)Endocytosis- the removal of materials from a cell i.Phagocytosis- engulf large particles ii.Pinocytosis- pinch in small amounts of liquids iii.Receptor-mediated endocytosis- molecules first bond with receptors on cell membrane and then are taken into cell vesicles.

c) Exocytosis- the removal of materials from a cell Exocytosis and Endocytosis Animation

Comparing the two…

d) Sodium-Potassium Pump- 3 positive sodium ions (Na + ) are pumped out of the cell for every 2 positive potassium ions (K + ) pumped into the cell. This means that there is more positive charges leaving the cell than entering it. As a result, positive charge builds up outside the cell compared to inside the cell. The difference in charge between the outside and inside of the cell allows nerve cells to generate electrical impulses which lead to nerve impulses.

Can you tell the difference?

Would you need energy? Yes… it is going from Low to High Concentration

Active vs. Passive Transport Active Transport Passive Transport Energy Required Direction Types YESNO LOW  HIGHHIGH  LOW Diffusion, Facilitated Diffusion, Osmosis Endocytosis, Exocytosis, Sodium- Potassium Pump

What is this process called?