Question

Extranuclear inheritance occurs in
A)Killer Paramecium
B)Killer Amoeba
C)Euglena
D)Hydra

Answer 1

Hint: The unit of inheritance (genes) are present in the nucleus. In some Eukaryotic species mitochondria and chloroplasts are also responsible for carrying out inheritance. This type of inheritance which occurs outside the nucleus is known as extra-nuclear inheritance.

Complete answer:
To solve this question, we must know about the extranuclear inheritance and in which species it occurs.
The extranuclear inheritance in animals takes place through mitochondria and in plants it occurs through mitochondria and chloroplast. The mitochondria and chloroplast have circular DNA which replicate independently during cell division.

Now let us discuss the organisms given in the question.
Killer Paramecium-The Killer paramecium has a granular particle present in the cytoplasm called the Kappa particles. These particles are inherited after sexual and asexual reproduction. The sexual reproduction takes place through conjugation in which the kappa particles move to the opposite sensitive strain. This is an example of extranuclear inheritance.
Killer Amoeba- Amoeba is a unicellular prokaryotic organism.
Euglena- It is a single celled eukaryote. It does not reproduce sexually.
Hydra- They mostly reproduce asexually. No extra nuclear inheritance is recorded.

Hence, the correct answer is option (A)

Note: The extranuclear transmission is seen in the genome of the virus. Example is perinatal transmission. It occurs from mother to fetus which begins before birth and ends one month after birth. The viruses carrying HIV or Hepatitis can pass to the fetus through bloodstream or through breast milk.