Blood clot. Coloured scanning electron micrograph (SEM) of a blood clot from the inner wall of the left ventricle of a human heart. Red blood cells (erythrocytes) are trapped within a fibrin protein mesh (cream). The fibrin mesh is formed in response to chemicals secreted by platelets (pink), fragments of white blood cells. Clots are formed in response to cardiovascular disease or injuries to blood vessels. Connective tissue (orange) is also seen.
Ruptured venule. Coloured scanning electron micrograph (SEM) showing stacks (rouleaux) of red blood cells exposed inside a torn venule. A venule is a very small blood vessel in the microcirculation that allows deoxygenated blood to return from the capillary beds to the larger blood vessels (veins). Red blood cells are the most abundant cell in the blood. They have no nucleus and are about 7 micrometers across. Magnification: x2300 when printed at 10 centimetres wide.
Moss spore capsule: Colored Scanning electron micrograph (SEM) of moss (Funaria sp) spore capsule. : pics
Coloured scanning electron micrograph (SEM) of rods (blue) and cones (red), the light sensitive cells in a human retina. Rods aid vision in dim light, while cones allow colour vision | Ralph C. Eagle, Jr. | SCIENCE PHOTO LIBRARY
Scanning electron micrograph (SEM) of cancellous (spongy) bone of the human shin. Bone tissue is either compact or cancellous. Compact bone usually makes up the exterior of the bone, while cancellous bone is found in the interior. Cancellous bone is characterised by a honeycomb arrangement of trabeculae. These structures help to provide support and strength. The spaces within this tissue normally contain bone marrow, a blood forming substance. Credit: SCIENCE SOURCE/SCIENCE PHOTO LIBRARY
Ruptured capillary. Coloured scanning electron micrograph (SEM) of a red blood cell squeezing out of a torn capillary. A capillary is the smallest type of blood vessel, often only just large enough for red blood cells to pass through. Red blood cells (erythrocytes) are biconcave, disc-shaped cells that transport oxygen from the lungs to body cells. Credit: STEVE GSCHMEISSNER/SCIENCE PHOTO LIBRARY
“Human Cerebral Cortex,” Alfonso Rodríguez-Baeza and Marisa Ortega-Sánchez, scanning electron microscope, 2009
Fertilization. Colored scanning electron micrograph (SEM) of a sperm (blue) attempting to penetrate a human egg (orange).
Colored scanning electron micrograph of the blood vessels coming from the optic disc. Way cool.
Brain tumour. Coloured scanning electron micrograph (SEM) of a glioma, a type of tumour that arises from glial cells of the central nervous system. The most common site for gliomas is the brain. They can be either low or high-grade, with the latter having the worse prognosis. Magnification: x8000 when printed at 10 centimetres wide. Credit: STEVE GSCHMEISSNER