In which of the following animals dimorphic nucleus is found?
- Amoeba proteus
- Trypanosoma gambiense
- Plasmodium vivax
- Paramecium caudatum
Answer
(4) Paramecium caudatum
Solution
Ciliated protozoans such as Paramecium have two types of nuclei (nuclear dimorphism):
Macronucleus – large, polyploid; controls the vegetative (metabolic) functions.
Micronucleus – small, diploid; concerned with reproduction (conjugation).
⇒ Amoeba, Trypanosoma and Plasmodium have only one type of nucleus.
∴ Dimorphic nucleus is found in Paramecium caudatum.
Answer: (4)