How does an Amoeba Obtain its Food?

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Anjali Mishra Content Writer-SME

Content Writer-SME

Amoeba has temporary arm-like projections that help in capturing food, changing shape and size, and acting as locomotion organs. An amoeba obtain its food through a process called endocytosis. There are two types of endocytosis- phagocytosis and pinocytosis.

Phagocytosis is a biological process through which a living cell engulfs or eats foreign particles. It is used by various cells as an important defense mechanism. The intake of fluids and small molecules by the cell through invagination of the cell membrane is called pinocytosis.

Thus, amoeba obtains its food through the process of endocytosis in which the amoeba engulfs its prey with the help of pseudopodia (false foot) and food vacuole. The food vacuole then fuses with lysosomes (organelles containing digestive enzymes) to break down the food and provide nutrients to the cell.

The process of endocytosis in amoeba is completed in five major steps- Ingestion, digestion, absorption, assimilation, and egestion.

  • Ingestion: The first step through which the amoeba obtains its food is ingestion. The amoeba engulfs the food through its pseudopodia and by forming a food vacuole.
  • Digestion: The breakdown of complex food particles into small digestible particles is done in this step. The step is catalysed by digestive enzymes present in amoeba. 
  • Absorption: The digested food is absorbed completely in this step. 
  • Assimilation: Like animals, amoeba also require energy to perform various specific functions like growth, movement and reproduction. For this they use the energy obtained from digested food.
  • Egestion: The final stage of nutrition in amoeba is excretion through which undigested foods are excreted by breaking the cell membrane.

Digestion in amoeba


Important Facts about Amoeba

Amoeba is an example of unicellular organism which belongs to the kingdom Protista. It is characterized by its ability to change its shape and move by extending and retracting pseudopodia, or temporary projections of cytoplasm

  • Some species of amoeba are pathogenic and can cause diseases in humans and other animals.
  • It is common in freshwater, soil, and aquatic environments and is an important component of many foods.
  • Pseudopodia in amoeba help it to perform specialized functions like movement and food intake.
  • It obtains their food through the holozoic mode of nutrition in amoeba.

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CBSE CLASS XII Related Questions

  • 1.
    (a) The insulin synthesised in our body is different from that synthesised by Eli Lilly company using recombinant DNA technology. Differentiate between them.
    (b) Why the insulin extracted from an animal source is not in use these days?


      • 2.
        Mention the number of chromosomes at each stage. Correlate the life phases of the individual with the stages of the process.


          • 3.
            Student to attempt either option (A) or (B):
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            (B) Explain GIFT and ICSI.


              • 4.

                Observe the given sequence of nitrogenous bases on a DNA fragment and answer the following questions:

                (a) Name the restriction enzyme which can recognise the DNA sequence. 
                (b) Write the sequence after restriction enzyme cut the palindrome. 
                (c) Why are the ends generated after digestion called as ‘Sticky Ends’?


                  • 5.

                    Flowering plants with hermaphrodite flowers have developed many reproductive strategies to ensure cross-pollination. Study the given outbreeding devices adopted by certain flowering plants and answer the questions that follow.

                    Note : All plants belong to the same species. No pollen tube growth/inhibition of pollen germination on stigma. Pollen germination on stigma.

                    • [(a)] Name and define the outbreeding device described in the above table.
                    • [(b)] Explain what would have been the disadvantage to the plant in the absence of the given strategy.


                      • 6.
                        (a) A bilobed dithecous anther has 200 microspore mother cells per microsporangium. How many male gametophytes can be produced by this anther?
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