Presentation on theme: "A Balancing Act: Direct and Indirect Active Transport"— Presentation transcript:
1 A Balancing Act: Direct and Indirect Active Transport
2 The Basics The cell is the coolest thing ever. A cell is picky about its living conditions.Intracellular K+ ion concentration is maintained at mM (35:1 inside to outside ratio).Intracellular Na + ion concentration is maintained at mM (0.08:1 inside to outside ratio).
3 Direct Active Transport: Sodium Potassium Pump Pump is a transmembrane protein composed of two α and two β subunits.Responsible for maintaining the sodium/potassium ion gradient.Pump uses ATP for energy, therefore it is also known as Na+/K+ ATPase.The sodium/potassium gradient is a key factor in nerve impulse transmission and protecting the cell from swelling.
5 Indirect Active Transport: Sodium/glucose Symporter Facilitates movement of glucose into blood via sodium/glucose symporter protein.Driven by uptake of sodium ions.Occurs in epithelial cells that line the intestine.Occurs when glucose concentration levels are lower than in the epithelial cells.
6 Steps of Na+/Glucose Symporter Cycle Pump open to outside of cell.Sodium ion bonds, leads to confirmation change.Glucose binds, another confirmation change.Pump opens to inside.Sodium falls off.Glucose falls off.Pump returns to original state.
8 ConclusionCells use direct and indirect active transport to maintain its “picky” lifestyle.Sodium potassium pump is an example of direct active transport.Sodium/glucose symporter is an example of indirect active transport.