Suppose polymerase chain reaction (pcr) is used to amplify a single dna marker on human chromosome 21. further suppose that a couple who have a child with down syndrome (trisomy 21) is examined for this marker. the mother has marker alleles of 310 and 380 bp. her mate has marker alleles of 290 and 340 bp.

i think the answer is

mass

meteorologists would compare a new weather map with one 24 h old to see how fast a front is moving.

is this a question? wassup

one part of the electromagnetic spectrum that arrives on earth as solar radiation from the sun is the visible spectrum. wavelengths of the visible spectrum combine to form what we refer to as

answer - d) ultraviolet radiation.

violet /   380–450 nm / 668–789 thz

violet is number 1 in the chart of visible light.