Applied Science
Material Type:
Rice University
Provider Set:
OpenStax College
Aneuploid, Aneuploidy, Autosomal Chromosome, Autosome, CentiMorgan, Chromosomal Theory, Chromosomal Theory of Inheritance, Chromosome 18 Inversion, Chromosome Aberration, Chromosome Disorder, Chromosome Identification, Chromosome Inversion, Chromosome Map, Chromosome Nondisjunction, Chromosome Number Disorder, Crossing Over, Crossover, Euploid, Gene Distance, Genetic Linkage, Genetic Map, Genetics, Homologous Recombination, Inheritance, Inherited Disorder, Karyogram, Karyotype, Linked Genes, Meiosis, Monosomy, Nondisjunction, Nonparental Type, Paracentric, Parental Type, Pericentric, Polyploid, Polyploidy, Recombinant Type, Recombination, Recombination Frequency, Sex Chromosome, Sex Chromosomes, Sex-linked Disorder, Sex-linked Genes, Sutton's Theory of Inheritance, Thomas Hunt Morgan, Three-point Test Cross, Translocation, Trisomy, Walter Sutton, X Inactivation, X-linked Disorders, X-linked Genes
Creative Commons Attribution


Electron micrograph shows a long, thin chromosome that has a banding pattern.
Chromosomes are threadlike nuclear structures consisting of DNA and proteins that serve as the repositories for genetic information. The chromosomes depicted here were isolated from a fruit fly’s salivary gland, stained with dye, and visualized under a microscope. Akin to miniature bar codes, chromosomes absorb different dyes to produce characteristic banding patterns, which allows for their routine identification. (credit: modification of work by “LPLT”/Wikimedia Commons; scale-bar data from Matt Russell)

The gene is the physical unit of inheritance, and genes are arranged in a linear order on chromosomes. Chromosome behavior and interaction during meiosis explain, at a cellular level, inheritance patterns that we observe in populations. Genetic disorders involving alterations in chromosome number or structure may have dramatic effects and can prevent a fertilized egg from developing.