Search results
In placental mammals, the presence of a Y chromosome determines sex. Normally, cells from females contain two X chromosomes, and cells from males contain an X and a Y chromosome.
- Telomeres of Human Chromosomes
In the 1930s, Hermann Muller was the first researcher to...
- Telomeres of Human Chromosomes
4 dni temu · Sex chromosome, either of a pair of chromosomes that determine whether an individual is male or female. The sex chromosomes of human beings and other mammals are designated by scientists as X and Y. In humans the sex chromosomes consist of one pair of the total of 23 pairs of chromosomes.
In 1905, Nettie Maria Stevens discovered the Y chromosome while she was studying mealworm genes. Image courtesy of the Carnegie Institution of Washington via Wikimedia Commons. Stevens guessed that the small chromosome she saw in male cells paired up with what Henking named the X chromosome.
14 mar 2012 · Specifically, there is a gene on the Y chromosome called SRY that makes a big difference. This gene tells the embryo to develop male features. Without the signals from the SRY gene, embryos develop into females. Biological sex arises from how cell use the genes on the X and Y chromosomes differently. (Shutterstock)
Some well-known human genes on the X chromosome are the following: Red-Green color blindness, due to missing or mutated genes for one of the two-color receptor proteins on the X chromosome. A third gene, for the blue color receptor protein, is located on chromosome 7 in humans.
Genes on the sex chromosomes can be expressed differently between males and females because of the presence of either single or double copies of the gene and because of the phenomena of different meiotic effects, X inactivation, and genetic imprinting.
26 paź 2020 · Actually, sex chromosomes and genetic expression vary widely, beyond a penis/vagina or XY/XX binary. XX and XY with the aforementioned expressions are the most common sex chromosomes and corresponding organs, but they’re not the only ones.
