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Last updated on Sep 26, 2022
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Answer
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Hint: A mature human sperm cell contains a haploid number of chromosomes. It is also known as ‘spermatozoa’. It is formed by a reduction division. The same number of chromosomes are also found in egg cells in females.
Complete answer:
A mature human sperm cell contains 23 chromosomes. In a diploid organism, like human beings, the body contains two sets of chromosomes that are 23 pairs and 46 in total. In such organisms there exist specialized cells called meiocytes.
Meiocytes undergo meiosis resulting in only a single set of chromosomes (23) getting incorporated into each gamete.
To know in detail let's study spermatogenesis.
The primary sex organs in males called testis produce gametes called sperms by the process of ‘spermatogenesis.’ The predecessors of this phenomenon are immature male germ cells also known as ‘spermatogonia’. Spermatogonia are located on the inside wall of seminiferous tubules. They multiply by mitotic division and increase in
numbers. Each spermatogonia is diploid and it contains 46 chromosomes. Some of the spermatogonia periodically undergo meiosis and are called ‘primary spermatocytes’. A primary spermatocyte completes the first reduction division resulting in the formation of two equal, haploid cells known as ‘secondary spermatocytes’. The second meiotic division then occurs in the secondary spermatocytes to form four equal, haploid ‘spermatids.’ These are transformed into spermatozoa by the process of
‘spermiogenesis.’ Spermatozoa contain 23 chromosomes.
So, the correct answer is ‘23.’
Note: -Meiosis is also known as a reduction division. Meiocytes are also called ‘gamete mother cells’.
-A haploid cell in human beings contains 23 chromosomes and a diploid cell contains 46 chromosomes.
-Each secondary spermatocyte has 23 chromosomes. Spermatids also contain a haploid number of chromosomes.
-Spermatogenesis begins at puberty and the resultant spermatozoa produced
are nothing but sperms.
Haploid describes a cell that contains a single set of chromosomes. The term haploid can also refer to the number of chromosomes in egg or sperm cells, which are also called gametes. In humans, gametes are haploid cells that contain 23 chromosomes, each of which a one of a chromosome pair that exists in diplod cells. The number of chromosomes in a single set is represented as n, which is also called the haploid number. In humans, n = 23.
Gametes contain half the chromosomes contained in normal diploid cells of the body, which are also known as somatic cells. Haploid gametes are produced during meiosis, which is a type of cell division that reduces the number of chromosomes in a parent diploid cell by half. Some organisms, like algae, have haploid portions of their life cycle. Other organisms, like male ants, live as haploid organisms throughout their life cycle.
They are not chosen, they represent an even half, a complete set of chromosomes.
The entirity of a cells genes (found on the chromosomes) is called a genome.
Somatic cells are the cells in our bodies that exclude sperm and egg. Sperm and egg are called germline cells.
The billions of somatic cells in a homo sapien have the same 46 chromosomes. 23 ( half) of them came from dad and 23 from mom. Thus we say somatic cells have two copies of each chromosome and it is abbreviated 2n. The germline cells are 1n or just n.
So your sperm has 23 chromosomes and after sexy time one of them can combine with an egg (which also has 23) to produce a cell(called a zygote) that has an entire complete genome (46). Then that zygote splits, and splits and splits.... And each time before it splits, all 46 chromosomes are copied (the copies are called sisters, or sister chromatids, respective to each other). The cells split into two new cells called daughter cell and each daughter has an entire genome. This form of cell splitting is called mitosis.
Probably the most important event in the cell cycle is the duplication of every DNA stand. This is called a Synthesis (S) phase. This is not a component of mitosis! It's a required event that happens before mitosis. So all 46 chromosomes get copied and then during mitosis each copy (an identical copy) is attached to each other at a region called the kinetachor. A kinetachor attaches sister chromatids (each sister is a copy of each other).
At the beginning of mitosis a web forms in the cell and you can think of the strands that make the web as sliding chains that can pull stuff from the center of the cell to 1 of two perimeter locations (poles) of the cell.
The chain like web attaches to the kinetachor and it rips apart the pair of chromosomes, rips apart the sisters. So that one sister goes to one side of the cell and the other sister chromosome goes to the other side of the cell. So now at opposite sides of the cell you have a complete genome (which will become the new daughter cells).
An identical process occurs in meiosis (specifically meiosis II) which is part of the process that forms the sperm and the egg. During meiosis however there's additional separation (separation of homologs which occurs in meiosis I) that occurs but it's really not pertinent to your question.