ACTIVE TRANSPORT:Transport of Large
molecules using energy
ATP
Active TransportRequires energy or ATPCan move materials from LOW to HIGH concentrationAGAINST concentration gradient
Proteins can pump molecules against the concentration gradient
(flow).
The protein uses ATP energy to push the molecules where the
cell NEEDS them to be, regardless of the concentration.
Label the protein pump on your cell membrane!
ACTIVE TRANSPORT EXAMPLE #1:
ACTIVE TRANSPORT EXAMPLE #2: ENDOCYTOSIS
Very large or bulk material (a lot at once) can be moved INTO the cell by a process called
ENDOCYTOSIS.
“en” like “enter”
There are two forms:PHAGOCYTOSISPINOCYTOSIS
Endocytosis – Phagocytosis
Used to engulf large items (biomolecules or pathogens) or bulk by creating a vesicle.Called “Cell Eating”
Phagocytosis - Capture of a Yeast Cell (yellow) by membrane extensions of an Immune System Cell, or white blood cell (blue)
Endocytosis – Pinocytosis Used to engulf large amounts of liquid by creating a vesicle.
Called “Cell drinking”
ACTIVE TRANSPORT EXAMPLE #2: EXOCYTOSISVery large or bulk material (a lot at once)
can be moved OUT the cell by a process called EXOCYTOSIS.
“ex” like “exit”
Moving the “Big Stuff”
Molecules are moved out of the cell by vesicles that fuse with the plasma membrane.
Exocytosis-
moving things out.
This is how many hormones are secreted and how nerve cells communicate with one another.
ExocytosisExocytic vesicle immediately after fusion with plasma membrane.