Question

How does amoeba obtain its food?
A) Endocytosis
B) Exocytosis
C) Endosmosis
D) Exosmosis

Answer 1

Hint: Amoeba is a unicellular organism. It has the tendency to change its shape by extending or retracting pseudopodia.

Complete Answer:
- Amoeba is a free living organism which does not have a cell wall. It is a prokaryotic organism. They do not have definite nucleus or other membrane bound organelles. The amoeba moves and feeds with the help of pseudopodia.
- The food sources of amoeba vary. Some live by consuming bacteria and other protists whereas some feed on dead and decaying organic matter.
- Amoeba ingests their food by extending the pseudopods. These extended pseudopods encircle and engulf live prey or particles. This process is called phagocytosis or endocytosis. Amoeba does not have a mouth.
- So phagocytosis can occur at any place in the cell. Once the prey is engulfed, amoeba secretes digestive enzymes to digest its food. The nutrition in amoeba is holozoic.

- When the cell is placed in a hypertonic solution, the water moves out of the cell and the cell becomes flaccid. This outward movement of water is called exosmosis.
- But if the cell is placed in a hypotonic solution, the water molecules move inside the cell. The cell gets charged with water and becomes turgid. This is called endosmosis.

Thus the correct answer is (A) Amoeba obtains its food by Endocytosis.

Note: Amoeba has false legs or pseudopodia. The pseudopodia engulf the food particles within the cell. Cell further secrete digestive juices for digestion of its prey.