Nutrition in Amoeba
An amoeba is a type of single-celled protozoal organism. Nutrition in an amoeba occurs through a process called phagocytosis where the entire organism pretty much engulfs the food it plans on eating up. The image below summarizes the stepwise process through which nutrition in amoeba occurs.
This food is mostly tiny bacteria, algae or other plant or dead animal matter available in the surrounding of the amoebas. One wonders how these amoebas, which do not have a mouth and no suction mechanism actually take in food since they’re just these shapeless cells.
Mode of Nutrition
The cell contents are enclosed by a shapeless cell membrane. Inside the cell, there is a dense nucleus, some bubble like contractile vacuoles, and all of these are surrounded by cytoplasm. When the amoebas sense some food nearby they move toward it with their pseudopodia (meaning false feet). The amoeba senses some food and gets ready to project itself towards the food particle.
The cytoplasm of the cell pushes the boundary of the cell membrane forming finger-like projections. These projections then engulf the food, forming a food vacuole. This vacuole is then transported deeper into the cell. Inside the food vacuole, digestive juices called enzymes are secreted. The enzymes process and help complete digest of the complex food molecules into simpler substances of soluble nature. After this, the nutrients are absorbed into the body of the amoeba through the wall of the food vacuole. This process is named diffusion.
The food literally diffuses into the cell body of the amoeba. In case the amoeba has ingested more food than it needs, the extra energy is stored in the cytoplasm itself. The undigested material remains in the food vacuole and now this unwanted material has to be excreted. Again, the cytoplasm pushes the vacuole towards the cell membrane boundary and the cell membrane at that part ruptures and the waste is ejected out.
The energy from this process is used to grow, reproduce, repair and perform other bodily functions just like other living organisms.
For information on nutrition in other microbes, download Byju’s- The Learning App.
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