Biology · Oct / Nov 2023 · Paper 41 · Question 2

lacteal ;

goblet (cell) ;

trachea / bronchi / bronchioles / AVP ;

any four from:

microvilli ;

(microvilli) provide a large surface area ;

epithelium / lining, one cell thick / thin / AW ;

ref. to diffusion ;

ref. to enzyme production ;

good blood supply ;

(good blood supply) to maintain a steep concentration gradient ; ref. to lacteal / N, and fat transport ;

AVP ;

hepatic portal vein ;

any two from:

unspecialised (cells) ;

that divide by mitosis ;

(to produce daughter cells) that become specialised (for specific functions) ;

any five from:

1

mitochondria are site of aerobic respiration ;

2

release energy ;

3

heart / intestine (cells), respire more ;

4

heart (cells) (continuously) contract ;

5

epithelial cells need more energy ;

6

active transport in the small intestine ;

7

red blood cells need space, for haemoglobin / oxygen ;

8

red blood cells, are moved in the blood / do not (actively) move ; 9

red blood cells, take up/ release, oxygen by diffusion ;

10 so no energy needed for active transport ;

11 idea that it is good if RBCs do not use up the oxygen they transport ; 12 AVP ;