Question

Which of these is called heterotypic division?
A. Meiosis I
B. Meiosis II
C. Mitosis
D. Amitosis

Answer 1

Heterotypic or reduction division is the division in which the one diploid cell is converted into two haploid cells.

Complete answer:
Cell division occurs by three methods- amitosis, mitosis and meiosis. In each division of the nucleus called karyokinesis occurs before the division of the cytoplasm termed as cytokinesis.
Amitosis is also known as direct cell division where nucleus and cytoplasm divide without the formation of chromosomes. It was first found in the red blood cells of chick embryos.
Mitosis occurs in somatic cells. These are the normal cells other than egg or sperm cells. It results in the formation of two daughter cells each with the same number and kind of chromosomes as the parent cell.
Meiosis I -The first process of meiosis starts with the separation of homologous chromosomes to become the halves of the chromosome number that means the reduction of diploid to haploid. The diploid chromosome becomes half and moves towards the equatorial plate during metaphase and this type of division is called heterotypic division because one diploid converts into haploid. It is much longer than meiosis II and is further divided into Prophase I, Metaphase I, Anaphase I, Telophase I and prophase I is divided into Leptotene, Zygotene, Pachytene, Diplotene and Diakinesis. Crossing over and chiasmata formation occurs in Prophase I. It is the phase responsible for the variation in the sexual reproducing organisms.
Meiosis II- The second process took place where the separation of the sister chromatids is done that was created by the replication of DNA during the interphase. The haploid chromosome divides and shifts to the metaphasic plate and this type of division is known as Homotypic division.

Hence, the correct answer is option (A).

Note: Meiosis is a special type of cell division which is seen in the case of sexually reproducing animals in this type of division there is formation of gametes such as egg or sperm cells. Basically there are two types of stages involved so it is called a two round process. In this first round is the main round where the reduction occurs where four cells are formed and one copy of each chromosome is haploid.