Biology 9700 · AS & A Level · Testing for biological molecules
Testing for biological molecules — practice question
Fig. 6.1 shows a diagram of the cell surface membrane of a squamous epithelial cell that lines an alveolus.
(a(i))[1]
A student measured line A-B and worked out the actual width of the membrane in Fig. 6.1. State the unit that should be used for the membrane’s actual width.
(a(ii))[1]
With reference to Fig. 6.1, state how the external surface of the cell surface membrane can be identified.
(b)[4]
Name R and S in Fig. 6.1 and describe what each does in the membrane.
Worked solution & mark scheme
This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Thickness in nanometres (nm)” …