Thekey differencebetween equational division and reduction division is thatequational division refers to meiosis II, during which the chromosomal number remains equal as单倍体。相反,还原分裂是指减数分裂I,在此期间,染色体的数量从二倍体状态减少到一半。
减数分裂是有性繁殖的重要过程。它促进了单倍配子的产生,以使每一代的遗传材料与上一代保持不变。它还确保了遗传上不同的产生配子,产生遗传变异。减数分裂是通过两个分裂发生的,因为减数分裂I和减数分裂II。在减数分裂I期间,染色体数量从二倍体减少到单倍体。因此,我们称此分区减少部门。在减数分裂II期间,染色体数量保持在单倍体状态。因此,我们将此部门称为方程式部门。
内容
1.Overview and Key Difference
2.什么是方程式部门
3.什么是减少部门
4.方程式和减少部门之间的相似之处
5。并排比较 - 表格形式的方程式与减少划分
6。概括
什么是方程式部门?
The equational division is the second division of meiosis. It is also known as meiosis II. Equational division begins from the two haploid cells produced by the reduction division. From two haploid cells, four haploid cells are produced in this phase. There is no change in the chromosome number of daughter cells. We call this phase equational division because it does not change the chromosome number of the cells.
Equational division resembles有丝分裂细胞分裂。During equational division, individual chromosomes line up at the metaphase plate without pairing with the homologous chromosomes. During anaphase, centromeres split and sister chromatids separate from each other. Sister chromatids then migrate towards the opposite poles. Therefore, chromosome number remains constant (n) as the previous cell. At the end of the equational division, four haploid cells are produced.
什么是减少部门?
Reduction division is the first division of meiosis. It is also known as meiosis I. As the name suggests, the chromosome number reduces in half. Therefore, the chromosome number decreases from diploid (2n) to haploid (n) state during the reduction division. There is a long interphase before meiosis I. Reduction division occurs via four subphases: prophase I, metaphase I, telophase I and anaphase I.
During prophase I, homologous chromosomes recognize each other and form pairs. Then they form tetrads and exchange their genetic material between them. During prophase I, genetic recombination takes place. Genetic recombination increases the genetic variability within a species. During anaphase I, homologous chromosomes migrate towards the opposite poles. Since homologous chromosomes migrate into each pole, the chromosome number becomes half. Each daughter cell has only one copy of each chromosome. At the end of reduction division, two haploid daughter cells are produced. Reduction division is followed by equational division.
What are the Similarities Between Equational Division and Reduction Division?
- 方程式和减少划分是减数分裂的两个划分。
- Both divisions produce haploid cells.
- Reduction division is followed by equational division.
- Both divisions have four subphases.
- There is no interphase between these two divisions.
- 它们发生在性繁殖过程中,在性细胞形成中,在精子发生和卵子发生中。
- Daughter cells resulting in each division are genetically different.
方程式和减少部门有什么区别?
In equational division, genetic material is transmitted equally into daughter cells. In reduction division, genetic material is reduced in half and transmits to daughter cells. So, this is the key difference between equational and reduction division. Furthermore, four daughter cells are produced at the end of an equational division, while two daughter cells are produced at the end of the reduction division.
此外,同源染色体配对和遗传重组在还原划分期间发生,而它们不发生在方程式中。因此,这是方程式和还原划分之间的另一个区别。
The below infographic lists all the important differences between equational and reduction division in tabular form.
摘要 - 方程式与减少部门
Two divisions of the genetic material take place during meiosis. These divisions are called reduction division (meiosis I) and equational division (meiosis II). In the reduction division, the chromosome number is reduced to half. In the equational division, chromosome number remains in the haploid state without reducing. Genetic material is transmitted equally into four daughter cells. Thus, this is the key difference between equational and reduction division.
Reference:
1.“减数分裂中还原和方程细胞分裂的概述。”stuce.com,Available here。
2. “Replication and Distribution of DNA during Meiosis.” Nature News, Nature Publishing Group,Available here。
Image Courtesy:
1. “Meiosis2” By Boumphreyfr – Own work(CC BY-SA 3.0)viaCommons Wikimedia
2. “Meiosis1” By Boumphreyfr – Own work(CC BY-SA 3.0)viaCommons Wikimedia
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