| 释义 |
metacentric, a.|mɛtəˈsɛntrɪk|
[ad. F. métacentrique, f. métacentre: see prec. and -ic.]
1. Of or pertaining to a metacentre.
1798Phil. Trans. LXXXVIII. 242 The curve..is termed the metacentric curve, being the line traced by the successive metacentres. 1881Times 6 Jan. 11/2 The result of the inclination at Pembroke is shown in a metacentric diagram.
2. Cytology. [-centric 2.] Of a chromosome: having the centromere in or near the centre.
1939C. D. Darlington in Jrnl. Genetics XXXVII. 357 Two sister chromatids would become the concurrent arms of a new metacentric chromosome. 1945,1946[see acrocentric a.]. 1962Lancet 2 June 1158/1 The 46 chromosomes..in the cultured cells of the blood of their patient included an unpaired metacentric chromosome. 1970Nature 5 Dec. 938/2 Somatic mouse cells have forty acrocentric and telocentric and no metacentric chromosomes.
Hence as n., a metacentric chromosome.
1945M. J. D. White Animal Cytol. & Evolution iv. 56 Whether such a metacentric could pass through an indefinite number of mitoses without being frequently disrupted is open to doubt. 1961Lancet 26 Aug. 463/2 The usual human Y..is normally about the same length as the smallest metacentric..or very slightly longer. 1971Nature 15 Oct. 481/2 The karyotype presented as typical by Kao and Puck was interpreted by them as having three hamster telocentrics replaced by two human metacentrics. |