a. disassembly following proteasomal degradation of intermediate filaments.
b. disassembly of lamin filaments following phosphorylation by mitotic cyclin/cdk complexes.
c. ubiquitination of mitotic cyclin proteins.
d. lamin filament dephosphorylation by cdc14.
a. The spindle elongates.
b. Kinetochores remain attached to shortening kinetochore microtubules.
c. Chromosomes move to the spindle equator.
d. The spindle poles move closer together.
1) A centromere is the tightly packed specialized region of DNA which is the point of attachment for two sister chromatids. It is made up of tightly wound DNA
The kinetochore is a multi-unit protein complex which attaches to the centromere and then this kinetochore attaches to the mitotic spindle which pull the sister chromatid apart during mitotic division.
2) The nuclear envelope contains a meshwork of laminin and this laminin after dephosphorylation by cyclin dependent kinase 2 turns into individual laminin dimers.
Hence the only answer is option B showing disassembly of lamin fibers by mitotic cyclin cdk complexes.
3 In anaphase A the mitotic spindle pulls the daughter chromosomes to the opposite end of the spindle by shortening of the microtubules attached to the kinetochore. The kinetochore stays attached to the mitotic spindle. Hence the answer is
Option B) The kinetochores remain attached to shortening kinetochore microtubules.
In most cells, where do all microtubules originate? What is the difference between a kinetochore and...
QUESTION 1 A gene that encodes a protein that stimulates progression of the cell cycle is known as a proto-oncogene. True False QUESTION 2 Cytokinesis occurs after which stage or phase of the cell cycle? a. G2 b. S c. G0 d. G1 e. M phase QUESTION 3 During cell-cycle checkpoints, protein kinases known as CDKs phosphorylate target proteins only when they associate with a cyclin. True False QUESTION 4 During mitosis, many of the spindle fibers attach to chromosomes...