Download Interesting Facts: • The drug Colchicine arrests cell cycle proression

NPTEL – Biotechnology – Cell Biology
Interesting Facts:
•
The drug Colchicine arrests cell cycle proression.
•
A disregulation of the cell cycle components may lead to tumor formation.
•
Several methods can be used to synchronise cell cultures by halting the cell cycle
at a particular phase. For example, serum starvation and treatment with thymidine
or aphidicolin halt the cell in the G1 phase.
•
Some organisms can regenerate body parts by mitosis. For example, starfish
regenerate lost arms through mitosis.
•
Some organisms produce genetically similar offspring through asexual
reproduction. For example, the hydra.
•
Although errors in mitosis are rare, the process may go wrong, especially during
early cellular divisions in the zygote.
•
Endomitosis is a variant of mitosis without nuclear or cellular division, resulting
in cells with many copies of the same chromosome occupying a single nucleus.
Questions:
Q1. If a person dies from ruptured aorta and is found to have a history of such deaths in
family. The gene for what protein is likely to be mutated in this patient?
A.
fibronectin
B.
heparin
C.
proteoglycan aggregate
D.
fibrillin
Q2. When a benign adenoma becomes a metastatic adenocarcinoma, which group of
molecules are almost certainly degraded by the tumor cells?
A.
collagen type I, II and III
B.
fibronectin and b2 integrins
C.
type IV collagen and laminin
D.
elastin, type IX collagen, and selectins
Q3. Chromosomes are duplicated during which phase of the cell cycle?
A. G1 phase
B. G2 phase
C. S phase
D. metaphase
E. prophase
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NPTEL – Biotechnology – Cell Biology
Q4. If a cell is in G2 then------A. it has twice the amount of DNA present in a telophase nucleus.
B. it has visibly distinct chromosomes.
C. it lacks a visible nuclear membrane.
D. it is in mitosis.
E. it is in cytokinesis.
Q5. The ____________ is responsible for the separation of the chromosomes during
____________ of mitosis.
A. cell wall; anaphase
B. flagellum; metaphase
C. mitotic spindle; anaphase
D. kinetochore; prophase
E. centromere; telophase
Q6. The ____ surrounds the cell like a belt, preventing the passage of substances between
the cells.
A.
B.
C.
D.
gap junction
desmosome
hemidesmosome
tight junction
Q7. During which stage does DNA replication occur?
A. Prophase.
B. Anaphase.
C. Metaphase.
D. None of those above.
Q8. Which of the following is NOT correct?
A. Mitosis is produces genetically identical cells.
B. Cytokinesis is a part of mitosis
C. Metaphase occurs before anaphase.
D. All somatic cells are produced by mitosis.
Q9. Match the terms with the appropriate stages in the answer: Migration, Shortening and
Thickening, Cytokinesis, Prophase.
A. Telophase, Anaphase, Prophase, centrioles forming.
B. Anaphase, Prophase, Metaphase, microtubules.
C. Anaphase, Prophase, Telophase, centrioles forming.
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NPTEL – Biotechnology – Cell Biology
D. Metaphase, Anaphase, Telophase, microtubules.
Further reading:
1. Alberts B, Johnson A, Lewis J, et al. 2008. Molecular Biology of the Cell (5th
ed.). Garland Science. USA.
2. Karp G. 2010. Cell and Molecular Biology: Concepts and Experiments, John
Wiley & Sons, Inc. USA.
3. Cooper G M, Hausman R E. 2007. The Cell: A Molecular Approach (4th ed.).
ASM Press,Washington, D.C.
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