The substances that Gross studied are maternal messenger RNA’s—products of certain of the maternal genes. He and other biologists studying a wide variety of organisms have found that these particular RNA’s direct, in large part, the synthesis of histones, a class of proteins that bind to DNA. Once synthesized, the histones move into the cell nucleus, where section of DNA wrap around them to form a structure that resembles beads, or knots, on a string. The beads are DNA segments wrapped around the histones; the string is the intervening DNA. And it is the structure of these beaded DNA strings that guide the fate of the cells in which they are located.
1. The passage is most probably directed at which kind of audience?
(A) State legislators deciding about funding levels for a state-funded biological laboratory
(B) Scientists specializing in molecular genetics
(C) Readers of an alumni newsletter published by the college that Paul Gross attended
(D) Marine biologists studying the processes that give rise to new species
(E) Undergraduate biology majors in a molecular biology course
2. It can be inferred from the passage that the morphogenetic determinants present in the early embryo are
(A) located in the nucleus of the embryo cells
(B) evenly distributed unless the embryo is not developing normally
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