Question

The genetic info in paramecium is contained in
A. Micronucleus
B. Macronucleus
C. Mitochondria
D. Both A and B

Answer 1

Paramecium is a single-cell organism with a shape that resembles a shoe's heel. It ranges from 50 to 300um in size and varies from species to species. It is found in a freshwater environment for the most part.

Complete Answer:
- It is a single-celled eukaryote that belongs to the Protista kingdom and is a well-known ciliate protozoa genus.
- It belongs to the Ciliophora phylum as well. The entire body is protected by tiny hair-like filaments called the cilia that assist in locomotion. There is also a profound oral groove containing oral cilia that is not so clear. This cilia 's main function is to assist both in locomotion and in dragging the food to its oral cavity.

In addition, the nucleus contains a macronucleus and a micronucleus.
1. Macro Nucleus: The kidney-like or ellipsoidal form of the macronucleus. The DNA (chromatin granules) is tightly packed within it. The macronucleus governs all the paramecium's vegetative functions, and is also called the vegetative nucleus.
- The macronucleus plays a part in the functioning of non-reproductive cells, including the expression of genes essential for the cell to function every day.

2. Micro Nucleus: Near the macronucleus, the micronucleus is located. It is a tiny and compact structure, spherical in form. Throughout the cell, the fine chromatin threads and granules are evenly distributed and regulate cell reproduction. The number varies from species to species in a cell. The nucleolus in the caudatum is not present.
- The micronucleus has the function of preserving genetic stability and ensuring that the desired genes are passed onto the next generation. It is also called the generative nucleus or germline.

The correct answer is option (A) Micronucleus.

Note: Paramecium, by binary fission, reproduces asexually. During replication, the micronuclei undergo mitosis, while the macronuclei break by amitosis. In the end, each new cell contains a duplicate of the macronuclei and micronuclei after transverse division of the cell. Reproduction can occur spontaneously through binary fission.