All cells arise from other cells through the process of cell division. Meiosis is a specialized form of cell division that produces reproductive cells, such as plant and fungal spores and sperm and egg cells. In general, this process involves a "parent" cell splitting into two or more "daughter" cells. In this way, the parent cell can pass on its genetic material from generation to generation. Based on the relative complexity of their cells, all living organisms are broadly classified as either prokaryotes or eukaryotes.
It involves two rounds of division that ultimately result in four cells with only one copy of each chromosome haploid. Additionally, prior to the division, genetic material from the paternal and maternal copies of each chromosome is crossed over , creating new combinations of code on each chromosome. Errors in meiosis resulting in aneuploidy an abnormal number of chromosomes are the leading known cause of miscarriage and the most frequent genetic cause of developmental disabilities. In meiosis, DNA replication is followed by two rounds of cell division to produce four daughter cells, each with half the number of chromosomes as the original parent cell. Before meiosis begins, during S phase of the cell cycle , the DNA of each chromosome is replicated so that it consists of two identical sister chromatids , which remain held together through sister chromatid cohesion.
In the famous words of movie character Forrest Gump, "Life is like a box of chocolates; you never know what you're gonna get. The same principle applies to human genetics. When the body forms sperm or egg cells in a special type of cell division called meiosis, our DNA mixes and matches in seemingly infinite and unpredictable combinations. Later, when just two of the great variety of sperm and egg cells meet, they produce children who are different from their parents.
There are two types of cell division: mitosis and meiosis. Meiosis is the type of cell division that creates egg and sperm cells. Mitosis is a fundamental process for life. During mitosis, a cell duplicates all of its contents, including its chromosomes, and splits to form two identical daughter cells.
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Rocky 2 years ago
I apologize, of course, but this does not suit me at all. Who else can help?
All сomments (2)
I apologize, of course, but this does not suit me at all. Who else can help?
Well done, what words ..., brilliant idea