Search results
Results from the WOW.Com Content Network
Chromosome 17 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. People normally have two copies of this chromosome. Chromosome 17 spans more than 84 million base pairs (the building material of DNA ) and represents between 2.5 and 3% of the total DNA in cells .
In most eukaryotes, a cell carries two versions of each gene, each referred to as an allele. Each parent passes on one allele to each offspring. An individual gamete inherits a complete haploid complement of alleles on chromosomes that are independently selected from each pair of chromatids lined up on the metaphase plate. Without recombination ...
Note that the pair of sex chromosomes may or may not be homologous, depending on the sex of the individual. For instance, females contain XX, thus have a homologous pair of sex chromosomes. This means that females have 23 pairs of homologous chromosomes in total (i.e., 22 pairs of non-sex chromosomes (autosomes), 1 pair of sex chromosomes).
The words homozygous, heterozygous, and hemizygous are used to describe the genotype of a diploid organism at a single locus on the DNA. Homozygous describes a genotype consisting of two identical alleles at a given locus, heterozygous describes a genotype consisting of two different alleles at a locus, hemizygous describes a genotype consisting of only a single copy of a particular gene in an ...
The paternal (blue) chromosome and the maternal (pink) chromosome are homologous chromosomes. Following chromosomal DNA replication, the blue chromosome is composed of two identical sister chromatids and the pink chromosome is composed of two identical sister chromatids. In mitosis, the sister chromatids separate into the daughter cells, but ...
Each chromosome carries many genes, with each gene occupying a different position or locus; in humans, the total number of protein-coding genes in a complete haploid set of 23 chromosomes is estimated at 19,000–20,000. [2] Genes may possess multiple variants known as alleles, and an allele may also be said to reside at a particular locus.
Polyploidy is a condition in which the cells of an organism have more than two paired sets of chromosomes. Most species whose cells have nuclei ( eukaryotes ) are diploid , meaning they have two complete sets of chromosomes, one from each of two parents; each set contains the same number of chromosomes, and the chromosomes are joined in pairs ...
In the diagram, (1) refers to a chromatid: 1-half of two identical threadlike strands of a replicated chromosome. During cell division, the identical copies (called a "sister chromatid pair") are joined at the region called the centromere (2). Once the paired sister chromatids have separated from one another (in the anaphase of mitosis) each is ...