1. Active Transport

2. Warm Up!
Imagine that a human blood cell, which is 3% salt, is placed in a beaker of pure water.
Draw a picture of this scenario
Is it in a hypertonic or hypotonic solution?
Will it shrink or swell? Why?

3. 100% H2O
solution
3% Na
97% H2O
Red Blood Cell
Hypotonic
Swell

4. Animal cells placed into a hypotonic solution will EXPLODE.
Red
Blood
Cell

5. Animal Cells
Animal cells placed into a hypertonic solution will SHRIVEL.
Hypertonic
Red
Blood
Cell

6. Plant Cells
In a hypotonic environment, the vacuole fills with water. Cell wall keeps it from exploding
Water
Cell
Wall
Central
Vacuole

7. Plant Cells
In a hypertonic environment (loss of water), the plasma membrane pulls away from the cell wall (vacuole empty).
Water
Cell
Wall
plasma membrane

8. To Do: Worksheet: Osmosis & Tonicity
“tonicity” means predicting how a cell will react in a solution (hypotonic, hypertonic, isotonic)

9. Active Transport
The movement of molecules across the plasma membrane using energy (ATP).

10. ATP Adenosine triphosphate Made in the mitochondria
Has high energy bonds
Bonds can be broken to release energy for use in the cell
4 volunteers, please!

11. When is Active Transport Needed?
1. Moving from LOW to HIGH concentration Called “against the concentration gradient” Requires Energy from ATP

12. Ex: Protein pumps
Some membrane proteins use energy to pump substances in and out of the cell.
Volunteers, please!

13. 2. Moving LARGE molecules into or out of the cell

14. Example: Endocytosis ENTRY into cell
Portion of the membrane surrounds or engulfs a large molecule outside cell.
Requires Energy from ATP

15. Types of Endocytosis Pinocytosis: endocytosis of liquids
Phagocytosis: endocytosis of particles

16. Example: White Blood Cell destroys bacteria

17. Example: Amoeba eating

18. EXPORT of materials OUT of the cell (wastes, cell products)
Exocytosis:
EXPORT of materials OUT of the cell (wastes, cell products)
- Requires Energy from ATP

20. Active Transport in the Human Body
Protein Pump
Nerve cells- Sodium Potassium Pump (electric signals)
Pinocytosis
Intestine cells absorb water/nutrients
Egg cell absorbs water/nutrients
Phagocytosis
White Blood Cells (aka phagocytes) engulf & destroy bacteria, viruses, old cells
Exocytosis
Release digestive enzymes
Release hormones
Waste

21. Closure
Write out the KEY TERMS that you learned today!