Friday, 27 January 2017

Holding on to your host

Moniezia expansa is primarily present throughout ungulates of Europe, Asia, Africa, America and Australia. This parasite has also been found in South American countries, including Peru and Argentina.

Like all cestodes, or tapeworms, M. expansa are flat with multiple segments of proglottids, used for producing gametes for reproduction. The adult bodies lack digestive tracts and are covered with microvilli to increase surface area for the absorption of nutrients. Moniezia expansa adults can reach lengths of 4 to 5 meters and are separated into three sections including the scolex, neck and strobila. The scolex is usually less than 1 millimeter, and contains suckers and hooks to assist in holding on to the host. The small neck produces immature proglottids, while the large strobila (main body) consists of a large chain of mature male and female proglottids.

Tuesday, 17 January 2017

Traveling back to the Jurassic period!

Antique sample of a Pterodactyl Rib under a Motic B1 upright microscope

Pterodactlys were winged reptiles who lived in the Jurassic period about 150 million years ago. The specimen is a portion of a transverse section of rib (approx. 1.8mm wide) and was taken from the slate mine area of Stonesfield (Oxford, England) and has been prepared as a thin section and dated June 1855. Pterosaur bones are difficult to cut and polish to a thin section without losing material. It is a testament to the preparer that the paleohistology details are clearly visible.

Wednesday, 11 January 2017

Potatoes are everywhere

Potatoes contain starch in the form of typical large oval spherical granules; their size ranges between 5 and 100 microns. Under the microscope, the granules can be seen clearly in polarized light.

Potato starch – also known as potato flour – is extracted from potatoes. The cells of the root tubers of the potato plant contain starch granules (leucoplasts). To extract the starch, the potatoes are crushed and the starch grains are released from the cells. The starch is then washed out and dried to powder. Potato starch has been produced in the same basic way for centuries – actually even the ancient Incas knew how to make potato starch.