Cell recognition: It has receptors for attachment with other cells through chemical signals. Secretion / Excretion: Responsible for secretion & excretion of various substances and these processes are similar to that of intake of material e.g. Trypanosomes excrete Trypanosin & oligopeptides to cross the blood brain barrier. Membrane bound structures exist for attachment / joining of cells e.g. fusion of gametes, places where flagella are attached. Flagella in trypanosomes are used to join with vector’s intestine.
Flagella & cilia are also called undulipoda. Flagella are whip like structure and composed of a central axoneme and outer sheath that originates from cell membrane. Axoneme consist of nine peripheral and one central pair of microtubules. Central tubules are singlets and peripheral are doublets. The axoneme originates from Kinetosome (basal body) and it lie in flagellar pockets. Complete unit of flagellum, kinetosome and associated organelles is called mastigont or a mastigont system. Some time flagellum bent back to form loosely attached structure cell surface known as undulating membrane. If Golgi body is connected by a parabasal filament to kinetosome it is known as Parabasal Body. A fibril that runs from kinetosome to nuclear membrane is called Rhizoplast. Entire complex of organelles and an associated nucleus is referred as Karyomastigont. Some flagellates (Kinetoplastida) have dark staining body of kinetoplast and is situated near the kinetosome. Pseudopodia: are temporary extensions of the cell membrane and found in amoebas. Its function is in locomotion & feeding. Filopodia: Rhizopodia: