Do zygotes have homologous chromosomes?

To produce the needed number of chromosomes in sperm and eggs, meiosis reduces the number of chromosomes by half. … When an egg and sperm are united during fertilization, the resulting zygote has 23 pairs of homologous chromosomes, one in each pair from the egg and one from the sperm.

Do zygotes have 2 sets of chromosomes?

The zygote is endowed with genes from two parents, and thus it is diploid (carrying two sets of chromosomes). … In fact, the genes of the new zygote are not activated to produce proteins until several cell divisions into cleavage.

Do gametes have a single pair of homologous chromosomes?

Homologous chromosomes have the same genes, though they may have different alleles. So, though homologous chromosomes are very similar, they are not identical. The homologous chromosomes are separated when gametes are formed. Therefore, gametes have only 23 chromosomes, not 23 pairs.

What is the main difference between Chromatin and chromosomes?

Chromatin is a complex formed by histones packaging the DNA double helix. Chromosomes are structures of proteins and nucleic acids found in the living cells and carry genetic material. Chromatin is composed of nucleosomes. Chromosomes are composed of condensed chromatin fibers.

Do gametes have chromosomes?

In humans, gametes are haploid cells that contain 23 chromosomes, each of which a one of a chromosome pair that exists in diplod cells. … Gametes contain half the chromosomes contained in normal diploid cells of the body, which are also known as somatic cells.

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Can a girl have XY chromosomes?

The X and Y chromosomes are called “sex chromosomes” because they contribute to how a person’s sex develops. Most males have XY chromosomes and most women have XX chromosomes. But there are girls and women who have XY chromosomes.

What is yy chromosome gender?

The Y chromosome is present in males, who have one X and one Y chromosome, while females have two X chromosomes.

How can you tell if a chromosome is male or female?

Typically in mammals, the gender of an organism is determined by the sex chromosomes. In the case of humans, this happens to be the X and the Y chromosomes. So as you may recall, if you are XX, you are female. If you are XY, you are male.

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