Calculate the actual diameter of the vein marked by the line X-Y. Show your working and give your answer in millimetres (mm).
A valve would be useful evidence that the vessel in Fig. 1.1 is a vein and not an artery. Describe three structural features visible in Fig. 1.1 that would identify it as a vein rather than an artery.
Explain how the following structural features of a capillary are linked to its function. The capillary wall consists of a single layer of squamous epithelial cells.
Explain how the following structural features of a capillary are linked to its function. The capillary lumen has a diameter of about $8\,\mu\text{m}$.
The inner lining of arteries and veins consists of a layer of epithelial cells supported by a layer of elastic and connective tissue. The epithelial cells can divide by mitosis. State the role of mitosis in cell division of epithelial cells.
Explain why the epithelial cells undergo mitosis and not meiosis.
Fig. 1.2 shows a cell in late prophase of mitosis. Complete Fig. 1.3 to show the same cell in the anaphase stage of mitosis.