Amoeba: Amoeba Proteus is found in muddy water at the bottom of ponds and ditches. It feeds on microscopic organisms smaller than itself or decayed food substances found in the water. There is no mouth or alimentary canal. When it comes across food particles, it immediately puts out a pseudopodium. This flows around the particles and becomes cup snapped. Finally , it engulfs the particles. This happens when the two ends of the pseudopodium meet and fuse. some water is also enclosed and the small cavity formed is called a food vacuole. The process is termed ingestion.
Enzymes from the cytoplasm of the cell are secreted into the food vacuole to digest the food. The soluble products formed diffuse from the vacuole into the cytoplasm. Undigested material is left behind and egested as waste.
Paramecium caudatum : This protozoan lives in muddy waters and feed on tiny microscopic organisms like bacteria and decayed food particles. The beating of the cilia against to water causes a current of water to enter the Fuller through a mouth like opening. It carries with it particles of food, which are taken into food vacuoles. These vacuoles move around in the cytoplasm. Digestive juices are secreted into the food vacuoles to digest the food. Digestion is thus intracellular.
The soluble nutrients diffuse into the cytoplasm while the undigested waste products are passed out through the anal pore. Digestion in paramecium is again said to be intracellular.
No comments:
Post a Comment