Describe how the structure of the nephron and its associated blood vessels are adapted to the process of ultrafiltration.

Mark scheme

Marking points from the official mark scheme (Oct/Nov 2018). The mark or mark type is shown in brackets.

1. [8] any eight from 1 capillary/glomerulus, endothelium ; 2 has, many/large, gaps/pores / holes / fenestrations ; 3 afferent arteriole wider than efferent arteriole ; 4 high, blood / hydrostatic, pressure in glomerulus ; 5 fluid forced, out of glomerulus / into Bowman's capsule ; 6 podocytes; 7 have interdigitating, processes / extensions ; 8 that form, filtration slits / slit pores ; 9 basement membrane ; 10 (mesh of) collagen / glycoprotein (fibres) ; 11 acts as (main), selective barrier / filter ; 12 large/RMM > 68 000, proteins / molecules, do not pass through; 13 (red/white blood) cells, do not pass through ; 14 water/solutes / ions, pass through;
2. [7] any seven from 1 two examples from: liver / muscle / adipose ; 2 increases glucose uptake; 3 increases permeability of cells to glucose ; 4 more, transport / GLUT (4), proteins (added to membrane) ; 5 by vesicles fusing with cell surface membrane ; 6 stimulates, glycogen synthesis / glycogenesis ; 7 glucokinase / hexokinase / glycogen synthase ; 8 lipid / triglyceride / fatty acid, synthesis stimulated ; 9 increase in respiration; 10 (so) more (facilitated) diffusion of glucose into (liver) cells ; 11 decreases, glycogenolysis / lipolysis / gluconeogenesis ; 12 decreases blood glucose concentration ;