Class 4 Science Vegetative Propagation Question Answer
Q- What is vegetative propagation?
Vegetative propagation is a form of asexual reproduction in plants where new individuals arise from vegetative parts such as roots, stems, and leaves, rather than from seeds.
Q- What are the types of reproduction through underground stems? Give one example for each.
- Types: Rhizomes and bulbs.
- Example: Rhizomes – Ginger; Bulbs – Onion.
Q- How does bryophyllum reproduce?
Bryophyllum reproduces through the formation of buds along the margins of its leaves. These buds can grow into new plants even while still attached to the parent plant.
Q- Define the terms – scion and stock.
- Scion: The upper part of a grafted plant that is attached to the rootstock, containing the desired traits.
- Stock: The lower part of a grafted plant, typically the root system, providing a stable base for the scion.
Q- Explain about reproduction through sub-aerial stems.
Sub-aerial stems, like runners, are thin, long stems growing horizontally above the ground. Nodes on runners have buds that can develop into new plants. Example: Strawberry plants produce runners.
Q- What are the natural methods by which plants reproduce asexually?
Plants reproduce asexually through various natural methods:Reproduction through Roots: Plants like sweet potato and dahlia produce new plants from detached roots.
- Reproduction through Underground Stems: Rhizomes (e.g., ginger) and bulbs (e.g., onion) can be cut into pieces with buds to grow new plants.
- Reproduction through Sub-aerial Stems: Runners (e.g., strawberry) have nodes with buds that form new plants.
- Reproduction through Suckers: Underground stems, like in chrysanthemum, produce new plants.
- Reproduction through Leaves: Some plants form buds in leaf margins, growing into new plants.
Q- What are the artificial methods by which plants reproduce asexually?
Artificial methods of asexual reproduction include:
- Cutting: A part of a plant with a node is cut and buried in the soil to form roots and shoots (e.g., rose, bougainvillea).
- Grafting: Joining healthy parts (scion and stock) of two plants to create a plant with combined features (common in trees and shrubs).
- Layering: Bending a flexible branch to the ground, encouraging it to root before separating it to form a new plant (e.g., grapes).
- Tissue Culture: Growing multiple plants from a single cell in a laboratory setting, allowing for rapid propagation.
Q- What are the advantages of asexual reproduction in plants?
Advantages include:
- Rapid Propagation: Large numbers of plants can be produced quickly.
- Genetic Uniformity: Offspring are genetically identical to the parent.
- Preservation of Desirable Traits: Desired characteristics are preserved in the new plants.
- Less Energy Requirement: No energy is spent on seed production.
Q- What are the disadvantages of asexual reproduction in plants?
Disadvantages include:
- Lack of Genetic Variation: Limited genetic diversity may make the population susceptible to diseases or environmental changes.
- Vulnerability to Uniform Threats: If a pathogen affects one plant, it can affect the entire population.
- Dependence on Parent Plant Health: Offspring depend on the health and adaptability of the parent plant.
- Limited Adaptability: Limited ability to adapt to changing environmental conditions.
Q: What is reproduction in plants?
A: Reproduction in plants is the process through which they produce offspring, ensuring the continuation of life from one generation to the next.
