Biology · Oct / Nov 2023 · Paper 42 · Question 1

haemoglobin ;

platelets ;

9.3 ;;;

any three from:

(salt) solution has a lower water potential than the (red blood) cells/ ora ; (diameter decreases because) water leaves the (red blood) cells by osmosis ;

water travels, from higher water potential to lower water potential / down a water potential gradient ;

across the, cell / partially permeable, membrane ;

any one from:

water potential (of red blood cells) is the same (as the salt solution) / AW ; no, net / overall, movement of water (across membrane / in or out of cell) ;

(red blood cells) do not have a (rigid) cell wall / ora ;

any two from:

transport (of ions / sucrose / AW) / translocation ;

as a reactant / (used in) photosynthesis ;

as a solvent / substances dissolve in it ;

medium for, chemical / enzyme / metabolic, reactions ;

support / (maintaining) turgidity (of cells) / (maintaining) turgor

pressure / prevent wilting ;

AVP ;