Active
Transport
Part 2
Active Transport
 Active
ATP
Transport: ATP (energy)
needed, Goes AGAINST the
concentration gradient (low  high)
 3 Types of Active Transport:
Protein pumps
 Exocytosis
 Endocytosis

Types of Active Transport
1. Protein Pumps: Proteins that
FORCE molecules into & out of cells
 Example: Sodium-Potassium Pump
 Remember “PumpKin”…
 3 Sodium (Na+) ions leave cell and
2 Potassium (K+) ions come in
Why is this useful??
Cell Pumps are important to our bodies because:
•They allow our nerves to send signals
•They prevent our cells from bursting with ions
•They allow our cells to grow
•They help our cells differentiate into different kinds of cells
Sodium Potassium Pump
What about when macromolecules are too big
for facilitated diffusion or active transport?
2. Exocytosis: molecules leave the
cell by fusing a vesicle with the
membrane to spit out the
contents. FLUID OUTSIDE CELL
Vesicle: portion
of cell membrane
that pinches off
to form a pouch.
Example: A hormone that has been created
needs to be secreted by the cell so it can
reach its target organ.
3. Endocytosis: Process by which
molecules enter the cell by making
a vesicle out of the cell membrane.
Example: A white blood cell engulfs (takes in)
a pathogen to destroy it with enzymes.
Check this Out!
 Animation
of Endo- and Exocytosis
Pair Share
Ridding the cell of materials by discharging
the materials in vesicles is called
A. osmosis.
B. diffusion.
C. exocytosis.
D. endocytosis.
