Question

Spirogyra belongs to: ____.

• A. Bryophyta
• B. Pteridophyta
• C. Algae
• D. Gymnosperm

Hint:

Spirogyra is commonly called "water silk" or "pond scum" because of its slippery, silky texture when touched in fresh water.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Plant classification breaks down different groups based on body differentiation, the presence of vascular tissues, and seed production capability.

Step 2: Detailed Explanation:
Spirogyra is a genus of filamentous, unbranched green algae belonging to the class Chlorophyceae. It is characterized by its unique spiral or helical arrangement of chloroplasts within its cells. Like other thallophytes (algae), its body lacks true roots, stems, or leaves, and it grows primarily in freshwater environments.

Step 3: Final Answer:
Spirogyra belongs to the Algae group.

Answer 2

The question asks which broad plant group Spirogyra belongs to, so each option is checked against Spirogyra's actual features.

1. Bryophyta: Bryophytes, like mosses, have a differentiated plant body with root-like, stem-like, and leaf-like parts and typically grow on land in moist places. Spirogyra has none of this differentiation and lives submerged in water, so it does not belong here.
2. Pteridophyta: Pteridophytes, like ferns, have true vascular tissue and well-developed roots, stems, and leaves. Spirogyra is a simple filament of cells with no vascular tissue at all, ruling this out.
3. Algae: Spirogyra is a filamentous green alga made of a single row of cylindrical cells, each containing a distinctive ribbon-shaped, spiral chloroplast (which is where its name comes from). Like other algae, it lacks true roots, stems, and leaves and lives in freshwater, matching this option exactly.
4. Gymnosperm: Gymnosperms are seed-producing plants such as pines and cycads, with woody stems and needle-like or compound leaves - a body plan completely unlike the simple filament of Spirogyra.

Spirogyra's undifferentiated, filamentous body with spiral chloroplasts is characteristic of the algae, not any of the more complex plant groups.

Therefore, the correct answer is Algae.