Calculate magnification and actual size from scale information, using proportional geometry to interpret biological images accurately in Cambridge A Level Biology questions.
In mammals, the small intestine is the main site of absorption of the products of digestion.
Fig. 2.1 is a transmission electron micrograph of a longitudinal section (L.S.) of part of an epithelial cell from the small intestine of a mammal.
Fig. 2.2 is a transmission electron micrograph of a horizontal section made at the position indicated by the two arrows in Fig. 2.1.
Fig. 2.1
Fig. 2.2
A scientist measured the length and the diameter of some of the microvilli shown in Fig. 2.1 to estimate the total surface area of microvilli on the surface of the epithelial cell.
The scientist assumed that each microvillus was cylindrical in shape.
Suggest one other measurement needed to estimate the total surface area of the microvilli of the epithelial cell.