Download Active Transport Pumps

Active Transport
Active Transport

Requires energy


in the form of ATP (useful cellular energy)
movement against the concentration gradient
2 methods of Active Transport
1.
2.
Pumps
Change in the cell membrane (endocytosis)
Active Transport Pumps:



Requires a protein channel called a “pump”
Requires ATP
Movement from low concentration to high
concentration

moving up the hill
hi concentration
low concentration

Works in the opposite direction of facilitated
diffusion.
Active transport pump

Energy (by way of ATP) forces materials through a
protein in the membrane against concentration
gradient.
Active Transport Pumps:

Two types of active transport pumps:


Proton pumps
Sodium/Potassium pumps
Both types require energy
Proton pump

Hydrogen ions are moved.
Sodium (Na+) / Potassium (K+)
Pump:


3 Na+ pumped out
2 K+ pumped in
http://www.brookscole.com/chemistry_d/templates/student_resources/shared_resources/animations/ion_pump/ionpump.html
Why Pump?


Nerve cells need a difference in ions (charge)
on either side of the membrane so they can
fire.
Which side of the cell membrane will have a
more “+” charge???
2 K+ in
3 Na+ out
Change in cell membrane
(2nd type of active transport process)

Endocytosis

Takes in (engulfs) large material

Cell membrane moves in until it encapsulates material,
becoming a vesicle.
Endocytosis: (IN)

Two types:


Phagocytosis
Pinocytosis
Phagocytosis:

“Cell Eating”


Pseudopods engulf material with
extensions of the cell membrane.
Ex. White blood cell taking in
foreign material for destruction.
Phagocytosis:
Pinocytosis:

“Cell Drinking”

Membrane wraps around a big
drop of solution (solute &
solvent) and pulls it in.
Pinocytosis:
Change in cell membrane
(2nd type of active transport process)

Endocytosis

Takes in (engulfs) large material


Cell membrane moves in until it encapsulates material,
becoming a vesicle.
Exocytosis

Vesicle that gets rid of large material
Exocytosis: (OUT)

Vesicle fuses with cell membrane, releasing
contents to outside of cell.


ex. Waste
ex. Digestive enzymes
Exocytosis: (OUT)
RNA
Rough ER
Golgi apparatus
Protein in vesicle
Plasma membrane
Figure 7.14 The formation and functions of lysosomes (Layer 1)
Figure 7.14 The formation and functions of lysosomes (Layer 2)
Figure 7.14 The formation and functions of lysosomes (Layer 3)