CELL TRANSPORT ( ACTIVE TRANSFOR)

by.

Alit Adi Sanjaya

Standard Competency:    

1.     To understand structure and function of cell as the smallest structures capable of basic life processes

Basic Competency:

1.3. To compare mechanism of membrane transport ( diffusion, osmosis, active  transport, endocytosis and exocytosis )

Indicator :

1. To differentiate mechanism of active and passive transport
2.  To explain process and give example of endocytosis and exocytosis
3. To design experiment with another material to gave evidence membrane transport
4. To make food preservative with membrane transport concept 

Membrane transport

No	Compere	Passive transport	Active transport
1	Molecule movement concept	Movement of a substance from a region of greater concentration to a region of lesser concentration.	Movement of a substance from a region of lesser concentration to a region of greater concentration.
2	Using cell energy	Without use cell energy	Use cell energy
3	Example	Diffusion and osmosis	Na and K pump, endocytosis and exocytosis

Endocytosis

That is substance enter to the cell. The examples are  pinocytosis and phagocytosis

·         Pinocytosis

Something in receptor membrane will adhere so happen dent in membrane. The dent will make sack.  free sack will stay in cytoplasm. This sack referred as  bubble of pinocytosis. bubble of pinocytosis  will dwindle become little bubble become larger ones bubble.

·         Phagocytosis

Phagocytosis represent food particles swallowing process and foreign cells by phagocytes and amoeba. Food or other particles will patch at membrane, last of membrane will form hollowing. Membrane will close and form sack. 

Exocytosis

Representing expenditure of vitamin from within cell. The example Secretion of digestive enzyme by digestive glad.

The K⁺ / Na⁺ Pump: An Example of Active Transport

Cellular [K⁺] is low and [Na⁺] is high - must pump K⁺ in and pump Na⁺ out  K⁺ and Na⁺ transport require ATP energy  Experimental evidence has shown that this pump will only work if [K⁺] is high on outside and [Na⁺] is high on inside.  This pump works independent of concentration gradient The pump is an integral membrane protein