Notes on Cilia and Flagella

Notes on Cilia and Flagella  This article provides useful notes about Ultrastructure, Variation, Chemical composition, Movement and Origin of Cilia and Flagella! The surface of certain cells is drawn out to form fine hair-like processes called cilia or flagella according to their length. Cilia (L., cili, eye lash) and flagella (L., little whip) are situated external to cytoplasm but have their origin from cytoplasm. Many protozoans,...

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Microtubules: Assembly, Function and Centrioles

Microtubules: Assembly, Function and Centrioles Microtubules have many features that distinguish them from microfilaments and intermediate fila­ments. To begin with, the outside diameter of a micro­tubule (usually about 25 nm) is much greater than that of microfilaments. Furthermore, microtubules are hol­low, containing a central lumen about 15 nm in diame­ter. Microtubule length is quite variable. Some micro­tubules are less than 200 nm...

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Hemal System in Star Fish

Hemal System in Star Fish Meaning of Hemal System: Asteroids, like other echinoderms, depend primarily on coelomic circulation for internal transport of gases and nutrients. In echinoderms, the blood vascular system is called hemal system, which is poorly developed in starfish and plays little role in circulation. The system consists of small fluid-filled sinus-channels that lack a distinct lining. The haemal channels are actually intercommunicating...

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