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The part of the digestive tract that begins with the caecum and ends where the rectum joins the anal canal. It is a sacculated, muscular tube which compacts undigested material into faeces for elimination, absorbing water into the blood stream during this process.
When we study the world around us and within us, we become aware of 'wholeness' at different scales. For example, we distinguish the whole person, the whole cell, the whole atom, and so on. We can identify patterns and regularities at each of these levels, and this has led to the concept of 'levels of organisation'.
This instrument allows examination of structures that are too small to seen with the unaided eye. A beam of light is shone onto or through the material and the image focused by glass lenses onto the eye or photographic film. (Further information and images)
Excess fluid drained from the tissues via lymphatic vessels and returned to the blood. Although generally a clear, watery fluid, lymph returning from the digestive tract contains digested fats and has a milky appearance.
These are vessels (sometimes abbreviated to 'lymphatics') carrying lymph away from tissues and towards the next set of lymph nodes. Many lymphatic pathways converge on the thoracic duct, which conveys lymph up through the thorax to return it to the blood stream in the large veins in the lower part of the neck on the left side. However, lymph from the right side of the head and neck, from the right upper limb, and from the right side of the thorax is returned to veins in the root of the neck on the right side.