Centrosome and Cilia, Flagella - UNSOLVED PRACTICE SET
Chapter: The Fundamental Unit of Life | Topic: Centrosome and Cilia Flagella
CENTROSOME AND CILIA, FLAGELLA - UNSOLVED PRACTICE SET
Topic: Centrosome and Cilia Flagella
Multiple Choice Questions
Q1. The centrosome is the main microtubule-organizing centre in:
- Plant cells only
- Animal cells only
- Both plant and animal cells
- Prokaryotic cells only
Q2. Centrioles are cylindrical structures composed of:
- Actin filaments
- Microtubules arranged in a 9+0 pattern
- Intermediate filaments
- Microfilaments
Q3. Cilia and flagella are hair-like projections that function in:
- Protein synthesis
- Cell movement and movement of fluids over cell surfaces
- Photosynthesis
- Lipid storage
Q4. The core of cilia and flagella, called the axoneme, has a characteristic arrangement of microtubules described as:
- 9+0 arrangement
- 9+2 arrangement
- 8+1 arrangement
- 7+2 arrangement
Q5. Which of the following cells typically has a single flagellum for locomotion?
- Paramecium
- Human sperm cell
- Tracheal epithelial cell
- Fallopian tube epithelial cell
Short Answer Questions
Q6. Describe the structure of a centrosome. What is its role during cell division?
Q7. Differentiate between cilia and flagella in terms of number, length, and function.
Q8. Explain the structure of the axoneme in cilia and flagella. What is the significance of the 9+2 arrangement of microtubules?
Q9. Why are centrioles absent in most plant cells? How do plant cells organize microtubules without centrioles?
Long Answer Questions
Q10. Draw well-labelled diagrams showing:
(a) The structure of a centriole (cross-section and longitudinal section)
(b) The structure of a flagellum showing the 9+2 arrangement of microtubules
Explain how the structure of centrioles and flagella supports their functions.
Q11. Describe the role of cilia in the human respiratory tract. How do cilia help protect the lungs from infection? What happens when ciliary function is impaired?
APPLICATION / ANALYSIS
Q12. Kartagener syndrome is a genetic disorder caused by defects in cilia and flagella. Affected individuals have immotile cilia and flagella.
(a) Why do males with Kartagener syndrome often experience infertility? Explain with reference to sperm structure.
(b) Why do these patients frequently suffer from respiratory infections? Explain the role of cilia in the respiratory tract.
(c) Interestingly, some patients with Kartagener syndrome have their internal organs reversed (situs inversus). How might defective cilia during embryonic development lead to this condition?
Q13. During a biology practical, a student observes two types of cells under a microscope:
Cell A: Has numerous short, hair-like projections covering its surface. The cell is stationary.
Cell B: Has one long, whip-like projection. The cell is moving rapidly in a circular motion.
(a) Identify the structures on Cell A and Cell B. Are they cilia or flagella?
(b) If Cell A is from the human trachea, what is the function of these projections?
(c) If Cell B is a protozoan like Euglena, how does the flagellum help it survive in its aquatic environment?