Question
Question: The figure given shows an amoeba that has been sliced into four parts. Which of the parts labeled pa...
The figure given shows an amoeba that has been sliced into four parts. Which of the parts labeled parts can still live and reproduce?
A. P
B. Q
C. R
D. S
Solution
All organisms are able to procreate and produce offspring. The mode of reproduction may be asexual or sexual. Some organisms can show both sexual and asexual modes of reproduction during their life cycle. Genetic variability is observed in organisms that reproduce sexually, while genetically identical individuals are produced due to asexual reproduction.
Complete answer:
-Amoeba is a single-celled microorganism found in water bodies. They have an irregular shape, lack cell walls, and have false feet called pseudopodia. They are able to move with the help of these pseudopodia. This movement is referred to as an amoeboid movement. The pseudopodia also aids in phagocytosis. The amoeba can engulf its food and ingest it this way. The inner components of the cell include cytoplasm, contractile vacuole, food vacuole, and nucleus.
-They undergo binary fission (asexual mode of reproduction). When it’s time to reproduce, the amoeba doubles its genetic content as in DNA replication takes place. The cell size also increases or the cell elongates. The nucleus divides and then the cell membrane moves inwards and cleavage is formed. The cytoplasm gets divided, this is called cytokinesis. This division of cytoplasm is not equal; hence, this type of binary fission is called irregular binary fission. This is also called amitotic division as the cytoplasm is not equally divided among the daughter cells.
-In this case, if the amoeba is spiced into four parts, the part containing the nucleus, the cytoplasm, and the cell membrane is viable. In this case, it is (R). This part will also be able to reproduce.
Hence, the correct answer is option (C).
Note: When the conditions are unfavorable the amoeba forms cysts to survive. The cell loses water content and becomes spherical. A hard cyst wall covers the cell. Once the situation is favourable the amoeba emerges out of the cyst. While some species of this microorganism are harmless there are a few that are pathogenic to humans. Entamoeba histolytica is one of them, this microorganism causes amoebiasis.