[kroh-muh-sohm] /ˈkroʊ məˌsoʊm/
any of several threadlike bodies, consisting of chromatin, that carry the genes in a linear order: the human species has 23 pairs, designated 1 to 22 in order of decreasing size and X and Y for the female and male sex chromosomes respectively.
any of the microscopic rod-shaped structures that appear in a cell nucleus during cell division, consisting of nucleoprotein arranged into units (genes) that are responsible for the transmission of hereditary characteristics See also homologous chromosomes
1889, from German Chromosom, coined 1888 by German anatomist Wilhelm von Waldeyer-Hartz (1836-1921), from Latinized form of Greek khroma “color” (see chroma) + -some (3)). So called because the structures contain a substance that stains readily with basic dyes.
chromosome chro·mo·some (krō’mə-sōm’)
chro’mo·so’mal (-sō’məl) or chro’mo·so’mic (-sō’mĭk) adj.
A structure in all living cells that consists of a single molecule of DNA bonded to various proteins and that carries the genes determining heredity. In all eukaryotic cells, the chromosomes occur as threadlike strands in the nucleus. During cell reproduction, these strands coil up and condense into much thicker structures that are easily viewed under a microscope. Chromosomes occur in pairs in all of the cells of eukaryotes except the reproductive cells, which have one of each chromosome, and some red blood cells (such as those of mammals) that expel their nuclei. In bacterial cells and other prokaryotes, which have no nucleus, the chromosome is a circular strand of DNA located in the cytoplasm.
- Chromosome band
noun 1. any of the transverse bands that appear on a chromosome after staining. The banding pattern is unique to each type of chromosome, allowing characterization chromosome band n. An area across the width of a chromosome that stains darkly or in a contrasting manner.
- Chromosome map
noun 1. a graphic representation of the positions of genes on chromosomes, obtained by observation of chromosome bands or by determining the degree of linkage between genes See also genetic map noun in genetics, a diagram showing the relative positions of the chromosome genes
- Chromosome mapping
chromosome mapping n. The process of determining the position of specific genes on specific chromosomes and constructing a diagram of each chromosome showing the relative positions of the genes.
noun, Genetics. 1. the characteristic number of chromosomes contained in the cell nucleus of a given species. noun 1. the number of chromosomes present in each somatic cell, which is constant for any one species of plant or animal. In the reproductive cells this number is halved See also diploid (sense 1), haploid