The reproductive mode of paramecium

Paramecium is a small, cylindrical, single-celled organism, composed of only one cell, androgynous, and the most common is paramecium, with a life span of about one day and night. because the shape of the body looks like the sole of an inverted straw sandal from a flat point of view, it is called paramecium. Let's take a look at the reproduction of paramecium.

Asexual reproduction

The asexual reproduction of paramecium is transverse two-division, which refers to the way in which a single cell divides and propagates along the transverse axis in asexual reproduction. The small nucleus first undergoes mitosis, then the large nucleus undergoes amitotic division, and then the middle part of the paramecium overflows into two new individuals.

Sexual reproduction

The main results are as follows: 1. In a certain environment, the mouth grooves of the two paramecium meet, the cell membrane fuses, part of the genetic information in the small nucleus is exchanged, and the conjugate reproduction begins.

2. The micronuclei in each individual undergo a meiosis to form four haploid micronuclei.

3. 3 of the 4 micronuclei of each individual disappeared, the remaining micronuclei split into a male nucleus (smaller) and a female nucleus (larger), and the large nucleus disappeared synchronously.

4. Two conjugated individuals exchanged male nuclei and fused with each other's female nuclei, and then the worm bodies were separated.

5. The fused new nuclei of each individual were divided for 3 times, each forming 8 nuclei, 4 forming new large nuclei and 4 forming new small nuclei.

6. 3 of the 4 new micronuclei disappeared, the micronucleus divided with the cytoplasm, and the macronucleus no longer divided.

7. After two times of micronucleus and cytoplasmic division, each individual formed 4 new individuals, resulting in a total of 8 new individuals.