ACTIVE TRANSPORT

LEARNING GOALS We need to understand the basic process of transport across a plasma membrane. We are learning... To understand the difference between passive and active transport

Active Transport Substances move from a region of low to high concentration Molecules are going AGAINST the concentration gradient and require ENERGY Nutrients like vitamins, glucose, and small proteins are taken in the cell in this process

Active Transport

ENERGY: ATP ATP: Adenosine Triphosphate Usable energy for the cell that is used in active transport created in the mitochondria through the process of cellular respiration

Active Transport Proteins Molecules such as glucose are transported into the cell by means of a protein pump Examples: 1. Sodium Potassium Pump 2. Hydrogen ion Pump

Sodium-Potassium Pump 3 Sodium (Na+) ions are pumped out of the cell with the help of ATP 2 potassium (K+) ions are pumped in of the cell with the help of ATP This pump ensures that nerve cells and muscle cells function properly by maintaining these concentration differences

ANIMATION hill.com/sites/ /student_view0/ chapter2/animation__how_the_sodium_po tassium_pump_works.html hill.com/sites/ /student_view0/ chapter2/animation__how_the_sodium_po tassium_pump_works.html

Bulk Transport Large quantities of material need to enter and exit the cell via Bulk Transport Use vesicles formed by the membrane to transport large quantities in and out of the cell All types of bulk transport requires energy in the form of ATP

Formation of a Vesicle

2 Types of Bulk Transport 1.Endocytosis – bringing large amounts of material inside the cell 2.Exocytosis – bringing large amounts of material out of the cell

Endocytosis Engulfing substances inside of the cell 2 Types: 1.Phagocytosis – cell eating 2.Pinocytosis – cell drinking

Endocytosis

ENDOCYTOSIS: Phagocytosis transport of solids into the cell The pseudopods (finger-like projections) enclose the material into a vesicle Lysosomes fuse with the vesicle and digest the contents and release nutrients into the cytoplasm

PHAGOCYTOSIS EXAMPLE White blood cells use phagocytosis to remove harmful bacteria from the blood and tissues

ENDOCYTOSIS: Pinocytosis Transport of fluids into the cell The cell membrane engulfs a drop of extracellular fluid to release into the cytoplasm Example: Pinocytosis brings cholesterol molecules into the cell

Endocytosis

Exocytosis bulk transport that releases material outside of the cellbulk transport that releases material outside of the cell Examples: Examples: Insulin is released into the bloodstreamInsulin is released into the bloodstream Protein packaging for transport out of cellProtein packaging for transport out of cell

Exocytosis

Protein Packaging

Animations of Passive & Active Transport!! ogy1111/animations/transport1.html ogy1111/animations/transport1.html hill.com/sites/ /student_view0/ chapter2/animation__phagocytosis.html hill.com/sites/ /student_view0/ chapter2/animation__phagocytosis.html