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| Nutrition in Amoeba |
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| Nutrition in amoeba is holozoic. Thus, solid food particles are ingested which are then acted upon by enzymes and digested. It is an omnivore, feeding on both plants and animals. Its diet includes bacteria, microscopic plants like the diatoms, minute algae, microscopic animals like other protozoa, nematodes and even dead organic matter. |
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| Since it is a unicellular organism, amoeba does not have any specialised structure or organ for the process of nutrition. It takes place through the general body surface with the help of pseudopodia. |
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| Ingestion |
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| The food is ingested at the point where it comes in touch with the cell surface with the help of pseudopodia. Pseudopodia engulf the food into the cytoplasm. The process of ingestion takes about two minutes. |
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| Some methods of ingestion reported in amoeba are |
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| Circumvallation - When the prey is active, a food cup is formed with the help of pseudopodia. |
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| Amoeba ingesting a paramoecium by circumvallation |
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| Circumfluence - When the prey is inactive and the amoeba rolls over it. |
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| Amoeba showing ingestion by circumfluence |
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| Import - The food passively sinks into the body on contact. |
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| Amoeba ingesting an algal filament by import |
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| Invagination - Pseudopodia secretes a sticky and toxic fluid which adheres and kills the prey. It is then taken in by invagination. |
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| Amoeba Ingesting by Invagination |
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| Pinocytosis - Also called cell drinking. There are pinocytosis channels at certain points through which the cell ingests the food. |
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| Amoeba Pinocytosis |
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