Chapter-8 - Adretek Stereology

Why is the use of stereological reports alone considered risky in biology compared with materials science?

It is mathematically impossible to calculate ratios in living tissue without a reference volume.

Materials science never uses reference volumes in its calculations.

Tissue shrinkage is common in biology and can skew ratios, creating the ‘reference trap’.

Biological structures are always isotropic, making ratios unnecessary.

According to the approach described for laminated structures, how is the average number of cells located beneath a unit of projected area (Na(cells,proj)) calculated?

By multiplying the number of cells in the layer by the average height of that layer: Nv(cells, layer) × h(layer).

By dividing the numerical density by the area of the vertical cross-section: Nv / Area.

By adding the average layer thickness to the surface density: h + Sv.

By multiplying the number of cells counted by the tissue shrinkage factor.

What is the necessary condition for correctly defining a Random Uniform Vertical (RUV) section in a layered material?

The horizontal reference plane must be parallel to the orientation of the strata.

The section must be strictly parallel to the upper surface of the specimen.

Rotation about the vertical axis must be fixed and not random.

The cross-section must be taken exactly at the centre of the reference volume.

If the linear dimensions of a fabric sample decrease by 5 per cent due to shrinkage, what impact does this have on the estimate of the projected area in relation to the volume?

Shrinkage affects the average height but does not affect the bulk density.

The projected area is not affected by the shrinkage; only the volume changes.

Both the volume and the projected area decrease by 15 per cent.

The projected area is reduced to 90 per cent of the original, whilst the volume falls to 85 per cent.

In the practical example of the epiphyseal growth plate, why is measuring the surface area of chondrocytes per unit of projected surface area of functional interest?

It simplifies the calculation by disregarding the distinction between the hypertrophic zone and the proliferative zone.

This is the only method that completely avoids the use of microscopes.

Cartilage is avascular, and metabolic exchanges depend on diffusion across the surface of the cartilage plate.

It enables the total number of cells in the rabbit’s entire skeleton to be counted accurately.