Chapter 3: The Nucleus
Which of the following facilitates breakdown of the nuclear envelope during the onset of mitosis?
a. Disassembly of nucleosomes in the associated constitutive heterochromatin
b. Increased export of material by the nuclear pore complexes into the perinuclear space
c. Phosphorylation of lamin subunits by a cyclin-dependent kinase (CDK)
d. Activities triggered at a restriction point late in G1
e. The activity of proteasomes
Binding of histone H1 proteins to importins is important for which of the following?
a. Transport through the nuclear pores complexes
b. Properly directed vesicular transport through the Golgi apparatus
c. Transport from the granular part of the nucleolus
d. Further binding to the “linker DNA” and proper assembly of nucleosomes
e. Phosphorylation of cyclins
Which of the following is a region of chromatin that is well developed in large neurons active in protein synthesis?
c. The Nissl substance (neuronal RER)
Which of the following is found during meiosis but not mitosis?
Transitions in the cell cycle from one phase to the next are regulated by protein kinases whose activity depends on what other proteins?
Mitotic figures visible in a tissue section from the lining of the small intestine are most likely to belong to which of the following categories?
a. Terminally differentiated cells
b. Partially differentiated cells