Meiosis 3D | Meiosis cell division I Meiosis and Mitosis |Prophase |Anaphase I Meataphse

Meiosis 3D | Meiosis cell division I Meiosis and Mitosis |Prophase |Anaphase I Meataphse | Telophase

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There are four phases in meiosis 1: prophase 1, metaphase 1, anaphase 1, and telophase 1. Additionally, there are four phases in meiosis two: prophase II, metaphase II, anaphase II, and telophase II.
One chromosome from each parent is spread out in two uncoilings in the chromatin. The chromatin's DNA multiplies and then condenses into the more recognizable X-shaped chromosomes.
Prophase1 begins with a diploid cell.
There are two uncoiled sets of chromosomes, one from each parent.
The more familiar X-shaped chromosomes are the result of the DNA in the chromatin replicating.
The replicated DNA is the same as the sister chromatids.
Synapsis is a process in which each chromosome pairs up with another.
A group of four sister chromatids are called a tetrad.
The genes are contained in the chromosomes.
These genes were passed down from parent to parent, and there are different versions of the same gene on each of the chromosomes.
The process of crossing over involves the exchange of chromatids from one allele to another.
In a process called crossover, the chromatids of each homologous chromosome exchange allelic segments. Crossover, also known as recombination, occurs randomly on each chromosome and results in a different combination of genes. This explains why each gamete is genetically different from the others. Hybridization creates genetic diversity in offspring. Therefore, children are different from their biological parents and biological siblings. As we enter prophase I, the nuclear envelope disappears, the centrioles move to the ends of the cell, and the spindle fibers unravel from them. Next, during metaphase1, the homologous chromosomes line up at the equator and attach to the spindle fibers from opposite poles. During anaphase 1, spindle fibers separate the homologous chromosomes in each tetrad and pull them to opposite poles of the cell. Cells enter telophase1, with one chromosome from each homologous pair at a different pole.
However, each chromosome is still composed of sister chromatids. Remember that the sister chromatids of each chromosome are no longer identical due to allelic exchange in crossovers. The spindle fibers then disappear and the nuclear envelope reforms around the chromosomes. Finally, cytokinesis occurs. Meiosis I ends with two genetically distinct haploid daughter cells. Each haploid cell contains only one set of chromosomes consisting of paired sister chromatids. Both cells now enter the next stage, meiosis II. However, unlike meiosis I, DNA is not replicated until meiosis II begins. Also in prophase II, the nuclear envelope disappears and spindle fibers fan out from the two sets of paired centrioles. During metaphase II, the chromosomes in each cell align at the equator and attach to spindle fibers at either pole. During anaphase II, the sister chromatids of each chromosome separate and migrate to opposite poles.
Once the sister chromatids separate, they are called chromosomes. Finally, in telophase II, the spindle fibers disappear, the nuclear membrane regenerates, and both cells undergo cytokinesis. Meiosis II ends with four genetically distinct haploid daughter cells, each containing only one set of chromosomes. Some points to remember about meiosis. It starts with diploid cells. Meiosis only produces gametes. Gametes are genetically distinct haploid cells, the sperm of the male and the egg of the female. Meiosis consists of two phases of cell division called meiosis I and meiosis II. During meiosis I, homologous chromosomes separate and form two haploid cells, each containing chromosomes in the form of paired sister chromatids. In meiosis II, the sister chromatids in the two cells separate and become separate chromosomes. Cell division of these cells produces four genetically distinct haploid gametes.
Meiosis 3D | Meiosis cell division I Meiosis and Mitosis |Prophase |Anaphase I Meataphse | Telophase
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