transport

Question 1

what is simple diffusion?

Answer 1

passive movement of solute from high to low concentration e.g. O2

Question 2

what is facilitates diffusion?

Answer 2

passive movement of ions and larger molecules across semi permeable membrane from high concentration to low with the aid of a channel protein e.g. glucose

Question 3

what is osmosis?

Answer 3

passive diffusion of water across a semi permeable membrane from a high water concentration go a low water concentration

Question 4

what happens in a hypotonic solution?

Answer 4

low solute concentration in solution therefore water flows into cell and it bursts

Question 5

what happens in a hypertonic solution?

Answer 5

high concentration of solutes in solution, water flows out of cell and it shrivels and becomes dehydrated

Question 6

what happens in an isotonic solution?

Answer 6

equal constant diffusion = no change in cell

Question 7

what is active transport?

Answer 7

the movement of molecules against a concentration gradient with ATP and the aid of a carrier protein

Question 8

what is bulk transport?

Answer 8

endocytosis and exocytosis

Question 9

what is endocytosis?

Answer 9

bull transport of molecules INTO cell as membrane engulfs and becomes a vesicle (uses ATP)

Question 10

what is exocytosis?

Answer 10

bull transport OUT of meolecules as a vesicle (uses ATP)

Question 11

why are cells small?

Answer 11

cells are small so they have a larger SA/V ratio, improving the efficiency of diffusion (small size/flat shape)