Puffball fungus spores, coloured scanning electron micrograph (SEM). These are the reproductive cells of the fungus. Magnification: x3000 when printed at 10 centimetres wide.

Deformed sperm cell. Coloured scanning electron micrograph (SEM) of a sperm cell with multiple tails. Magnification: x5000 when printed at 10 centimetres wide.

Activated platelet. Coloured scanning electron micrograph (SEM) of an activated platelet, or thrombocyte, from peripheral blood. Magnification: x2, 500 when printed at 10 centimetres wide.

Puffball fungus spore, coloured scanning electron micrograph (SEM). This is the reproductive cell of the fungus. Magnification: x3000 when printed at 10 centimetres wide.

Fossil debris in chalk. Coloured scanning electron micrograph (SEM) of a fossilised fragment of a coccolithotrope skeleton. Magnification: x8000 when printed at 10 centimetres wide.

Ureter lining. Coloured scanning electron micrograph (SEM) of the surface of a squamous epithelial cell from the ureter. Magnification: x6, 500 when printed at 10 centimetres wide.

E. coli bacteria. Coloured scanning electron micrograph (SEM) of Escherichia coli bacteria (orange) on a gecko's tongue. Magnification: x8000 when printed at 10 centimetres wide.

Pluripotent stem cell. Coloured scanning electron micrograph (SEM) of a pluripotent stem cell derived from a macrophage white blood cell. Magnification: x4000 when printed at 10 centimetres wide.

Cancer cell dividing. Coloured scanning electron micrograph (SEM) of a colorectal cancer cell dividing. It is in late telophase. Magnification: x4000 when printed at 10 centimetres wide.

Pluripotent stem cell. Coloured scanning electron micrograph (SEM) of a pluripotent stem cell derived from a macrophage white blood cell. Magnification: x4000 when printed at 10 centimetres wide.

Cancer cell dividing. Coloured scanning electron micrograph (SEM) of a colorectal cancer cell dividing. It is in late telophase. Magnification: x4000 when printed at 10 centimetres wide.

Rod-shaped bacterium. Coloured scanning electron micrograph (SEM) of a rod-shaped (bacillus) filamentous bacterium from a human mouth. Magnification: x1350 when printed at 10 centimetres wide.

Cat flea (Ctenocephalides felis), coloured scanning electron micrograph (SEM). Magnification: x50 when printed at 10 centimetres wide.