chromosome

[kroh-muh-sohm]

noun

Genetics.

1. 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 sex-determining chromosomes.

chromosome

/ ˈkrəʊməˌsəʊm /

noun

1. 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

chromosome

1. 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.

Other Word Forms

• chromosomal adjective
• chromosomally adverb
• interchromosomal adjective
• interchromosomally adverb
• nonchromosomal adjective

Word History and Origins

Origin of chromosome¹

First recorded in 1885–90; chromo- + -some ³

Example Sentences

A new review suggests that vitamin D supplements may help protect the ends of our chromosomes, known as telomeres, which play a vital role in slowing the aging process.

Read more on Science Daily

Researchers suspected that the mutation causing the condition was somewhere on the X chromosome, because females, which have two X chromosomes, are less affected.

Read more on The Wall Street Journal

At her 10-week appointment, she learned that her child had triploidy, a genetic condition where a fetus has three sets of chromosomes instead of two, and would miscarry late-term or die at birth.

Read more on Salon

However, this egg is not ready to be fertilised by sperm as it already contains a full suite of chromosomes.

Read more on BBC

People with this particular DSD have male XY chromosomes, but some are recorded as female at birth.

Read more on BBC