Eye color: The myth. One of the oldest myths in human genetics is that having blue eyes is determined by a single gene, with the allele for blue eyes recessive to the allele for non-blue eyes (green, brown, or hazel).Many people who know nothing else about genetics think that two blue-eyed parents cannot have a brown-eyed child.ye color: The myth. One of the oldest myths in human genetics is that having blue eyes is determined by a single gene, with the allele for blue eyes recessive to the allele for non-blue eyes (green, brown, or hazel).
Micrometer Caliper. a measuring instrument whose conversion mechanism consists of a screw-nut micropair. Micrometer calipers are used to measure linear dimensions by the absolute contact method.omplete turns are read from a scale marked on the hub of the micrometer caliper, and fractions of a turn are read from a circular scale marked on the drum. A displacement of the screw of not more than 25 mm is optimum because of the difficulty of manufacturing a screw with an accurate pitch over a greater length.
or calliper. 1. Usually, calipers. an instrument for measuring thicknesses and internal or external diameters inaccessible to a scale, consisting usually of a pair of adjustable pivoted legs. 2. any of various calibrated instruments for measuring thicknesses or distances between surfaces, usually having a screwed or sliding adjustable piece.