The Wellcome Image Awards recognise scientists who have created beautiful images as part of their own research and made them available for public use through the Wellcome Library. Click on the images for a larger version.

Colour-enhanced image of a housefly (Musca domestica) on sugar crystals. To eat the sugar the fly releases its enzyme-containing saliva onto it, lets it digest, then sucks it all back up. Houseflies are well known for carrying gastrointestinal diseases such as Salmonella and dysentery, but they can also spread tuberculosis, anthrax and other major illnesses through their habit of visiting decaying organic matter and faeces, as well as humans and their food.
Colour-enhanced scanning electron micrograph by Dave McCarthy and Annie Cavanagh.

Colour-enhanced image of red blood cells leaking out of a ruptured blood vessel. This is due to a mutation in the Ephrin-B2 gene, which prevents smooth muscle cells from being arranged correctly in the blood vessel wall. The blood vessels then become more fragile, leading to an increased rate of haemorrhaging. This abnormality is similar to that seen in the blood vessels that feed developing cancers. Understanding this process may help to lead to new cancer treatments.
Colour-enhanced scanning electron micrograph by Anne Weston.