autosome

n. any chromosome that is not a sex chromosome. A human normally has a total of 44 autosomes (arranged in 22 homologous pairs) in the nucleus of each body cell, although irregular numbers may occur through the loss or addition of one or more autosomes. If a homologous pair of autosomes has an extra chromosome, the condition is called trisomy. If one member of a homologous pair is absent, the condition is called monosomy.

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Psychology term of the day

January 19th 2025

short-wavelength pigment

the photopigment present in one of the three populations of retinal cones that has maximum sensitivity to a wavelength of 419 nm. The absence of the gene for the short-wavelength pigment causes tritanopia, a form of color blindness in which blue and green are confused with one another. See also long-wavelength pigment; medium-wavelength pigment.