Asexual Reproduction - UNSOLVED PRACTICE SET
Chapter: Reproduction in Organisms | Topic: Asexual Reproduction Binary Fission Budding Fragmentation
ASEXUAL REPRODUCTION - UNSOLVED PRACTICE SET
Topic: Asexual Reproduction Binary Fission Budding Fragmentation
Multiple Choice Questions
Q1. Binary fission in Amoeba involves:
- The fusion of two gametes
- Division of the parent cell into two equal daughter cells after nuclear division
- Breaking of the body into multiple fragments
- Formation of a small outgrowth that detaches
Q2. In budding, as seen in yeast and Hydra:
- The parent organism breaks into many pieces
- A small outgrowth called a bud develops on the parent body, receives a copy of the nucleus, and eventually detaches to become a new individual
- Two parents fuse to form a zygote
- Spores are released into the air
Q3. Fragmentation is commonly observed in:
- Humans and dogs
- Spirogyra, Planaria, and some fungi
- Birds and reptiles
- Flowering plants only
Q4. During binary fission in bacteria, the replication of the circular DNA occurs:
- After the cell divides
- Before the cell divides, ensuring each daughter cell receives a complete copy
- Only in one daughter cell
- In the cytoplasm without involving the nucleus
Q5. The main reason why Planaria can regenerate a complete organism from a small body fragment is:
- It has a simple body plan with specialised cells that can dedifferentiate and redifferentiate
- It has no cells
- It reproduces only sexually
- It has a hard exoskeleton
Short Answer Questions
Q6. Describe binary fission in Amoeba with a simple diagram in words. How does it differ from multiple fission seen in Plasmodium?
Q7. What is budding? Explain the process in yeast, mentioning the role of the nucleus in the formation of the bud.
Q8. Differentiate between fragmentation and regeneration. Why is true regeneration considered a more complex process than simple fragmentation?
Q9. A student observes a Hydra under the microscope and sees a small outgrowth on its body. Is this outgrowth a bud or a tentacle? How can the student distinguish between the two?
Long Answer Questions
Q10. Explain the three main types of asexual reproduction — binary fission, budding, and fragmentation — with detailed descriptions of the process in representative organisms (Amoeba, yeast/Hydra, and Spirogyra/Planaria). Compare these methods in terms of the number of offspring produced, energy requirement, and the role of mitotic cell division.
Q11. "Asexual reproduction is not always as simple as it appears." Discuss this statement by explaining: the cellular and molecular events during binary fission (DNA replication, karyokinesis, cytokinesis), the significance of unequal cytokinesis in budding, the role of specialised cells in regeneration, and why some organisms show combinations of asexual methods (like Hydra showing both budding and sexual reproduction).
APPLICATION / ANALYSIS
Q12. Case Study — Laboratory Culture Comparison:
A microbiology laboratory grew three organisms under identical conditions for 24 hours:
| Organism | Starting population | Reproduction method | Population after 24 hours |
|---|---|---|---|
| Bacterium A | 100 cells | Binary fission (every 20 min) | ? |
| Yeast B | 100 cells | Budding (every 2 hours, but only 80% successfully detach) | ? |
| Planaria C | 10 individuals | Fragmentation (each fragment into 3 pieces, 70% regenerate) | ? |
Answer the following:
(a) Calculate the approximate population of Bacterium A after 24 hours, assuming ideal conditions. Show your reasoning.
(b) Calculate the final population of Planaria C. Why is the percentage lower than theoretical expectation?
(c) If you were designing an experiment to compare growth rates, why would you need to control temperature and nutrient availability? Explain the biological basis.
Q13. Real-Life Application — Aquarium Maintenance:
Priya has a home aquarium with:
- A colony of Hydra that appeared on a plant she bought from a local pet shop
- She finds the Hydra population growing rapidly
- She also has small fish fry (baby fish) in the same tank
- She reads that Hydra can harm small fish with their stinging tentacles
Answer the following:
(a) Why is the Hydra population growing so rapidly in the aquarium? Explain the reproductive advantage of budding in this closed environment.
(b) If Priya removes half the Hydra manually, why will the population likely recover quickly? What biological property of Hydra makes this possible?
(c) Suggest one biological control method (using another organism) that Priya could introduce to manage Hydra without using chemicals. What characteristic should this control organism have?