Medical Sciences (including General Medicine, Physiology, Anatomy, General Pathology, Histology)
Depending on the university and faculty, the Medical Sciences modules taught in the UK may cover the basics of general medicine, or include more specialised subjects such as Physiology, Anatomy, General Pathology, Histology. Depending on the topic of your essay, various resources (books, reviews, research articles) from multiple fields of science should be consulted. Although many 1st-2nd year modules in the UK cover only basics of this science (and thus most information for your essay could be found in the books recommended to you by your module tutor), additional research on your topic in resent scientific publications is always welcomed.
Clear well-defined structure with logical and coherent flow of information is critically important. Your essay should tell a “story”, which would include basic well-established facts, recent findings (which might, on some occasions, contradict the existing dogmas), their interpretations and relevant scientific theories (either old or newly formulated), gaps in knowledge and potential future research directions needed to fill these gaps. Lots of new findings published these days challenge the existing views.
Whatever topic of medical sciences you are writing about, you should keep in mind that human body is a complex interconnected and tightly regulated system. No organ, tissue or cell exists in isolation. Every disease affects the whole body, even though the manifestations can be more clearly observed only in some body systems and parts. Emphasizing these connections in your essay would significantly improve its quality.
Research data and examples selected for essay should follow the logics of your essay. They should be not just relevant, but arranged in an order that helps to illustrate the right points at the right time. This would make the essay easily readable and understandable. Ability to communicate your thought clearly is always one of the points your essay will be marked for.
Obviously, the structure, depth and complexity of essay depend on the particular task at hands. The requirements for short undergraduate work and postgraduate dissertation are very different. But the major “selling” points mentioned above are always highly appreciated.