Chapter 2- The Cell; Memebrane Transport

Question 1

What are the two kinds of Transport membrane ?

Answer 1

1. Passive transport(diffusion , Osmosis) no energy is needed to
   move the substance.
2. Active Transport (active transport, transport in vesicles) energy is
   needed to move the substance

Question 2

What is the concentration gradient ?

Answer 2

1. It is a difference in the concentration of a chemical from one
   place to another.
   e.g from the inside to the outside of the plasma membrane.
2. Moving substances in and out by being selectively permeable
   where concentration ingredients can be formed and maintained.

Question 3

What is diffusion?

Answer 3

1. substance moves from an area of a greater concentration to
   an an area of lesser concentration; e.g 02 and co2 diffuse
   through the cell membrane.
2. movement of molecules across the plasma membrane down their
   concentration gradient.
3. both solvent and salutes undergo diffusion (move down their
   concentration ingredients).
4. across the plasma membrane , molecules can move straight or go
   through membrane proteins.

Question 4

Osmosis is only uses water , explain ?

Answer 4

1. diffusion in which there is a net movement of a solvent
   (water) through a selectively permeable membrane.
2. passive movement of water across a selectively permeable plasma
   membrane from an area of high concentration to an area of low
   concentration.
3. only occurs when membrane is permeable of water and not to
   certain solutes.

Question 5

What is active processes?

Answer 5

1. movement of a substance across a membrane against its
   concentration gradient.
2. energy is used need it to pump it in or out the cell.
3. movement is through membrane bound proteins.

Question 6

What active transports use?

Answer 6

• energy - ATP required

- low concentration - high concentration

Question 7

What is vesicle?

Answer 7

• it is a small spherical sac that carry out protein or molecule.

Question 8

What are the 3 kinds of transport in vesicles ?

Answer 8

1. Endocytosis- Extracellular materials that are brought into the
   cell in a vesicle formed by the plasma membrane.
2. Exocytosis- formed in a cell fuse with the plasma membrane and
   release materials out of the cell.
3. Phagocytosis- as form of Endocytosis in which the cell engulfs large solid particles like bacteria, viruses, worn-out cells