Description
T. saginata is normally 4 m to 10 m in length, but can become very large, over 12 m long in some situations. The body is whitish in colour, divided into the anterior scolex, followed by a short neck and a highly extended body proper called the strobila. Unlike other tapeworms, the scolex does not have a rostellum or scolex armature. It is composed of four powerful suckers. The strobila is composed a series of ribbon-like segments called proglottids. The segments are made up of mature and gravid proglottids. T. saginata is the largest of genus Taenia, consisting between 1000 to 2000 proglottids, and can also have a lifespan of 25 years in a host's intestine. The mature proglottid contains the uterus (unbranched), ovary, genital pore, testes, and vitelline gland. It does not have a digestive system, mouth, anus, or digestive tract. It is also an acoelomate, meaning it does not have a body cavity. In the gravid proglottid, the uterus is branched and filled with eggs. The gravid segments detach and are passed in the feces. Each of these segments can act as a worm. When they dry up, the proglottid ruptures, and the eggs are released. The egg can only infect cattle, the intermediate host. Inside the cow's duodenum, the oncosphere hatches with the help of the gastric and intestinal secretions, and migrates through the blood to the muscle. There it develops into infective cysticercoid cysticerci.
Read more about this topic: Taenia Saginata
Famous quotes containing the word description:
“As they are not seen on their way down the streams, it is thought by fishermen that they never return, but waste away and die, clinging to rocks and stumps of trees for an indefinite period; a tragic feature in the scenery of the river bottoms worthy to be remembered with Shakespeare’s description of the sea-floor.”
—Henry David Thoreau (1817–1862)
“God damnit, why must all those journalists be such sticklers for detail? Why, they’d hold you to an accurate description of the first time you ever made love, expecting you to remember the color of the room and the shape of the windows.”
—Lyndon Baines Johnson (1908–1973)
“Why does philosophy use concepts and why does faith use symbols if both try to express the same ultimate? The answer, of course, is that the relation to the ultimate is not the same in each case. The philosophical relation is in principle a detached description of the basic structure in which the ultimate manifests itself. The relation of faith is in principle an involved expression of concern about the meaning of the ultimate for the faithful.”
—Paul Tillich (1886–1965)