These proteins can have different functions in the body. For instance, some proteins such as keratin, which is found in hair and nails, are structural. Other proteins may serve as enzymes — molecules that help certain chemical reactions in the body. Yet others can play a role in passing messages from one cell to another cell signalling molecules or in protecting humans against disease e.
In scientists around the world announced the results of an immense collaborative scientific effort, the final sequencing of the entire human genome — a sequence of around 3 billion base pairs. This was a scientific breakthrough of immense importance. Thanks to these volunteers, scientists now understand more about human genetic information, genes — a field of study called genomics. Eventually, further genomic studies should help scientists to develop better diagnostic tools and treatments.
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.
Gametes contain half the chromosomes contained in normal diploid cells of the body, which are also known as somatic cells. So most animal cells and plant cells are diploid.
Then they're diploid in part because they got one chromosome from their mother and one chromosome from their father, therefore making them diploid. A haploid cell only has one set of chromosomes, and most of the time that refers to the so-called sex cells, either eggs or sperm. And these are [a] critical transition from a diploid cell to a haploid cell to allow normal reproduction to occur, so that when these two haploid cells come together with a single set of genetic information--single chromosomes--they can come together into a so-called zygote made of when the egg cell and the sperm cell come together that then reconstitutes a diploid cell, which can then become a new individual.
Nearly all the cells in the human body carry two homologous, or similar, copies of each chromosome. The only exception is cells in the germ line, which go on to produce gametes, or egg and sperm cells. Germ line cells are haploid, which means they contain a single set of chromosomes. In diploid cells, one set of chromosomes is inherited from the individual's mother, while the second is inherited from the father.
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