Active Transport
 Molecules move across the
membrane AGAINST their
concentration gradient
 (Low to High)
 ENERGY is required.
 2 Types:
1. Protein Pumps
LOW
2. Bulk Transport
HIGH
Protein Pumps
 Transport small molecules and ions AGAINST their
concentration gradients (LOW  HIGH) using ATP
(cell energy).
Bulk Transport
 Larger molecules (proteins,
starch) are transported by
vesicles.
 Endocytosis: vesicles
move substances in.
 Exocytosis: vesicles move
substances out.
Vesicle Fusion with Cell Membrane
Phagocytosis & Pinocytosis
“cell eating”
“cell drinking”
*Special types of endocytosis.*
BrainPOP: Active Transport
 http://www.brainpop.com/science/cellularlifeandgenetic
s/activetransport/preview.weml
Homeostasis
Homeo = like or similar
Stasis = balance or equilibrium
 The process by which an organism’s internal
environment is kept in equilibrium, or stable, in spite
of changes in the external environment.
 Examples:
 Internal Temperature (sweating removes excess body heat)
 Water Balance (kidneys adjust water amount in urine)
 A physical response to stress (breathing & heart rate
increases, pupils dialate, sweating)
BrainPOP: Homeostasis
http://www.brainpop.com/health/bodysystems/homeostas
is/