HAEMOGLOBIN AND BLOOD

Red blood cells This image shows red blood cells, clearly displaying their biconcave disc shape. Credit: Annie Cavanagh, Wellcome Images.

Blood bag BIGPICTUREEDUCATION.COM A laboratory technician holding a blood bag that contains group A, Rh-positive blood ready for transfusion. Credit: Wellcome Library, London BIGPICTUREEDUCATION.COM

Sickle-cell anaemia BIGPICTUREEDUCATION.COM Sickle-cell anaemia is a blood disease that causes the cell to form a characteristic sickle shape. This change in shape affects the cell's ability to carry haemoglobin. This image shows a normal red blood cell (background, coloured red) and red blood cell affected by sickle-cell anaemia (foreground). Credit: EM Unit, UCL Medical School, Royal Free Campus, Wellcome Images BIGPICTUREEDUCATION.COM

Sickled and other red blood cells A scanning electron micrograph image of sickled and other red blood cells, shown coloured red. Credit: EM Unit, UCL Medical School, Royal Free Campus, Wellcome Images

Molecular model of haemoglobin and sickle cell disease A molecular model of haemoglobin affected by sickle cell disease. Credit: T Blundell and N Campillo, Wellcome Images..

Ruptured blood vessel A colour-enhanced image of red blood cells leaking out of a ruptured blood vessel. This is due to a mutation that causes the blood vessels to be more fragile than normal, leading to an increased rate of haemorrhaging. Credit: Anne Weston, LRI, CRUK, Wellcome Images

Colour-enhanced blood clot This image shows many red blood cells and a single white blood cell held together in a meshwork of fibrin (brown). Credit: Anne Weston, LRI, CRUK, Wellcome Images 

Blood clot on a sticking plaster A scanning electron micrograph image of the underside of a sticking plaster that has been used to treat a razor blade cut. Red blood cells (shown in red) and thin fibres of the protein fibrin (beige) can be seen between the gauze fibres of the plaster (blue-grey). Fibrin is a protein formed from the conversion of clotting factors in the blood; the fibrin fibres trap blood cells and platelets to form a solid clot. This not only prevents further bleeding but also protects the open wound from infection. Credit: Anne Weston, LRI, CRUK, Wellcome Images  

Blood clot forming over a wound A colour-enhanced scanning electron micrograph image of a blood clot with squamous tissue visible beneath. As a blood clot on a surface injury dries out, it forms a protective scab over the wound, allowing new skin to grow underneath. Credit: David Gregory and Debbie Marshall, Wellcome Images

Blood clot A scanning electron microscope image of a blood clot that shows red blood corpuscles and fibrin. Credit: David Gregory and Debbie Marshall, Wellcome Images

Blood clot and new cells under fibrin A scanning electron microscope image of blood clot, showing new cells under fibrin clot. Credit: David Gregory and Debbie Marshall, Wellcome Images

Fibrin blood clot A scanning electron microscope image of a blood clot, showing new cells under a fibrin clot. Fibrin, which is also called Factor 1a, acts as a mesh and forms blood clots (with platelets) to trap blood cells and prevent further loss of blood as the wound heals. Credit: David Gregory and Debbie Marshall, Wellcome Images

Red blood corpuscles, discoid and stimulated platelets A scanning electron microscope image of red blood corpuscles, discoid and stimulated platelets. Credit: David Gregory and Debbie Marshall, Wellcome Images

Blood corpuscles in clot A scanning electron micrograph image of red blood corpuscles and a single white blood cell entangled in the fibrin mesh of a clot. Credit: David Gregory and Debbie Marshall, Wellcome Images

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