Radio Stars. Quasars are the brightest and most distant objects in the known universe. In the early 1960's, quasars were referred to as radio stars because they were discovered to be a strong source of radio waves. In fact, the term quasar comes from the words, quasi-stellar radio source.
The following DNA sequence occurs in the nontemplate strand of a structural gene in bacterium (the promoter sequence is located to the left but is not shown): 5 -GAATGTCAGAACTGCCATGCTTCATATGAATAGACCTCTAG-3 What is the ribonucleotide sequence of mRNA molecule that is transcribed from this piece of DNA?
Nondisjunction is a faulty cell division, which results in an embryo with three number 21 chromosomes instead of two. Prior to, or at, conception, a pair of number 21 chromosomes, in either the sperm or the egg, fail to separate. As the embryo develops, the extra chromosome is replicated in every cell of the body.