chromosomes

Cultural  

1. The small bodies in the nucleus of a cell that carry the chemical “instructions” for reproduction of the cell. They consist of strands of DNA wrapped in a double helix around a core of proteins. Each species of plant or animal has a characteristic number of chromosomes. For human beings, for example, it is forty-six.

---

Discover More

In humans, sex is determined by two chromosomes: an X-chromosome, which is female, and a Y-chromosome, which is male. (See sex chromosomes.)

Example Sentences

"We discovered that, in some species, large chunks of DNA on five chromosomes are flipped -- a type of mutation called a chromosomal inversion," said senior author Hennes Svardal from the University of Antwerp.

From Science Daily • Apr. 1, 2026

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

From BBC • Mar. 31, 2026

Even men who lack Y chromosomes still have a copy of the SRY region on one of their X chromosomes, which accounts for their maleness.

From Los Angeles Times • Mar. 26, 2026

Yet humans have little to no Neanderthal DNA on our X chromosomes -- one of two human chromosomes that determines an embryo's sex.

From Barron's • Feb. 26, 2026

This explained the mechanics of HeLa’s immortality: telomerase constantly rewound the ticking clock at the end of Henrietta’s chromosomes so they never grew old and never died.

From "The Immortal Life of Henrietta Lacks" by Rebecca Skloot