Why sperm cell and ovum contain 23 single chromosomes?

Answer 1

A daughter cell with only 23 chromosomes is called a haploid cell; these are the gametes (sex cells) which are produced during meiosis (note: this is not the same as mitosis). When a sperm & an ovum fuse at conception, the result is a single cell called a zygote, which now has 46 chromosomes - and is therefore a diploid cell.

Answer 2

First of all, who are the "parents"? Are they humans? Or another organism? If they are humans, sperm and egg cells have half the amount of chromosomes as the original cell. Also, sperm and egg cells are haploids, and are only 2 out of the 46 chromosomes a human would have. The other 44 are autosomes.

This question is a big FAIL. Please word your questions better. Quite confusing.....

Answer 3

The average human has 46 chromosomes which come directly from his or her parents. Therefore, one half (23 chromosomes) of his or her chromosomes comes from the mother, and the other half comes from the father. This is why the egg and sperm cell only carry 23 chromosomes each: because, when they merge together, the two groups of chromosomes are combined to form the fertilized egg, which will become a new individual.

Answer 4

In typical autosomal (body) cells, there are 46 chromosomes (23 paired chromosomes). In egg and sperm cells, there are only 23 because each is unpaired; being sex cells, they will only require one set of chromosomes to fertilize or be fertilize and produce a healthy mature cell with 46 chromosomes (23 from egg, 23 from sperm).

Answer 5

The daughter cells will have 46 chromosomes after meiosis I and 23 after meiosis II.

During Meiosis I, a germline cell doubles its DNA, so it would go from 46 to 92 chromosomes. When the cell divides, the daughter cells would have 46 chromosomes. In Meiosis II, the DNA does not replicate, so when these cells divide, the daughter cells only have 23 chromosomes.

Answer 6

Meiosis is also know as reduction division. The usual cell in the human body contains 46 chromosomes. In the production of gametes (sperm cells or egg cells), thee number of chromosomes is reduced to half. Conveniently, that half contains one of each type chromosome; therefore, when one gamete combines with another, called fertilization, the resulting cell again has 46 chromosomes.

Answer 7

So when they form a zygote that zygote has the full compliment of 46 chromosomes.