2.1.5 active transport

Question 1

define active transport

Answer 1

the net movement of particles into or out of a cell from a region of lower concentration to one of higher concentration

Question 2

what type of process if active transport

Answer 2

active process; it requires ATP supplied by aerobic respiration from mitochondria
it uses carrier proteins

Question 3

describe the process of active transport into a cell

Answer 3

mol bonds to CP receptor outside cell
ATP binds to CP inside cell
ATP hydrolysed into ADP and Pi; releases energy
causes protein to change shape
Pi binds to protein to hold new shape
mol enters cell
Pi released from protein; recombines with ADP into ATP
protein returns to OG shape

Question 4

what is the role of carrier proteins in active transport

Answer 4

each one is specific to the mol/ion it transport
makes it a selective process

Question 5

why can’t carrier proteins be involved in AT without ATP

Answer 5

their shape prevents moving against concentration gradient
receptors are on side which has lower conc

Question 6

what factors affect active transport

Answer 6

number of proteins
speed of each proteins
rate of respiration = E provided faster means faster rate of AT

Question 7

explain the process of endocytosis

Answer 7

bulk transport of materials INTO cells
requires ATP
material gets close to cell mem and forms a cavity around it
mem folds itself around material + pinches off to engulf substance
creates a vesicle

Question 8

explain the process of exocytosis

Answer 8

bulk transport of materials OUT OF cells
requires ATP
vesicle moves towards cell mem + fuses with it
causes substance to be released outside cell or into membrane

Question 9

what is the importance of the cytoskeleton for exo/endocytosis

Answer 9

is allows vesicles to move around cell to enter/exit

Question 10

what parts of bulk transport require ATP

Answer 10

vesicle movement, cells changing shape (to engulf materials), and fusion with cell mem.