A plant which has a horizontal underground stem is
A. rhizome
B. corm
C. creeper
D. tuber
Correct Answer:A
Explanation
The correct option is A. rhizome.
Detailed Explanation:
Definition of a Rhizome:
A rhizome is a type of underground stem that grows horizontally. It serves as a storage organ and a means of vegetative reproduction. Rhizomes can produce new shoots and roots at nodes, allowing the plant to spread and colonize new areas.
Characteristics of Rhizomes:
Growth Pattern: Rhizomes grow horizontally beneath the soil surface. They can produce new shoots that emerge above ground, which can develop into new plants.
Storage: They store nutrients and energy, which helps the plant survive adverse conditions.
Examples: Common examples of plants with rhizomes include ginger (Zingiber officinale), bamboo, and certain types of grasses.
Why the Other Options are Incorrect:
B. Corm:
A corm is a swollen underground stem that is typically short and thick. Unlike rhizomes, corms grow vertically and are not horizontal. They serve as storage organs but do not spread horizontally like rhizomes. Examples include taro and crocus.
C. Creeper:
A creeper refers to a plant that grows along the ground or climbs over surfaces. While some creepers may have horizontal stems, they are not specifically classified as underground stems. Creepers often have stems that can root at nodes but are not primarily underground structures.
D. Tuber:
A tuber is a swollen part of a stem or root that stores nutrients. Tubers grow underground but are typically not horizontal. They are more bulbous and can produce new plants from "eyes" (buds). Examples include potatoes and yams. Tubers do not have the same horizontal growth pattern as rhizomes.
Summary of Key Points:
Rhizome: Horizontal underground stem, capable of vegetative reproduction and nutrient storage.
Corm: Vertical swollen stem, not horizontal; serves as a storage organ.
Creeper: Plant that grows along the ground; not specifically an underground stem.
Tuber: Swollen storage organ, typically bulbous and not horizontal.
Revision Summary:
A rhizome is a horizontal underground stem that allows for vegetative reproduction.
Corms, creepers, and tubers have different structures and growth patterns.
Understanding the differences between these plant structures is crucial for identifying plant types and their adaptations.
Remember that rhizomes are key for plants that spread and colonize areas effectively.