Becker's World of the Cell 9th Edition by Lewis Kleinsmith, Jeff Hardin, Gregory Paul Bertoni

Exercise 13

Nucleoli. Indicate whether each of the following statements is true (T)or false (F). If false, reword the statement to make it true.
(a)Nucleoli are membrane-bounded structures present in the eukaryotic nucleus.
(b)The fibrils seen in electron micrographs of nucleoli contain DNA and RNA.
(c)The DNA of nucleoli carries the cells tRNA genes, which are present in clusters of multiple copies.
(d)A single nucleolus always corresponds to a single nucleolus organizer region (NOR).
(e)Nucleoli become heavily radiolabeled when radioactive ribonucleotides are providedT:o the cell.
(f)In animals and plants, the disappearance of nucleoli during mitosis correlates with cessation of ribosome synthesis.