Q.67 Important characters of Batrachospermum are
A. fresh water habitat
B. sexual reproduction is of advanced oogamous type
C. chantransia stage is found
D. monospore produced from chantransia stage
Choose the correct answer from the options given below:
(A) A, B only
(B) A, B, C, D only
(C) A, C, D only
(D) C, D only
The correct answer is (B) A, B, C, D only.
Detailed Character Analysis
A. Freshwater habitat: True—Batrachospermum is a cosmopolitan freshwater red alga found in clean, flowing streams, springs, and oligotrophic waters (not marine).
B. Sexual reproduction advanced oogamous type: True—Oogamy with large non-motile eggs in oogonia and small flagellated spermatia from antheridia (advanced anisogamy).
C. Chantransia stage found: True—Complex life cycle includes Chantransia phase (prostrate, filamentous sporophyte stage).
D. Monospore produced from Chantransia stage: True—Chantransia produces monosporangia → monospores → develop into gametophyte (Batrachospermum phase).
E missing: No E option; all A-D confirmed as key characters.
Option Breakdown
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(A) A,B only: Incomplete—misses life cycle stages C,D essential for identification.
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(B) A,B,C,D only: Correct—encompasses habitat, reproduction, and triphasic life cycle.
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(C) A,C,D only: Wrong—excludes oogamy (B), hallmark of advanced reproduction.
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(D) C,D only: Wrong—omits habitat/reproduction basics.
Introduction: Batrachospermum Key Features
Batrachospermum important characters include freshwater habitat, advanced oogamous sexual reproduction, Chantransia sporophyte stage, and monospore production—distinguishing this freshwater red alga from marine Rhodophyta. Known as “frog spawn alga,” essential for NEET phycology MCQs testing A-D options.
Core Batrachospermum Characteristics
1. Habitat (A): Clean, cool, flowing freshwater (streams 19 cm/s velocity); prefers acidic, low-nutrient oligotrophic waters. Absent in standing/marine habitats.
2. Reproduction (B): Oogamous—large non-motile eggs (oogonia) fertilized by flagellated spermatia; carpogonium → gonimoblast → carposporangia.
3. Life Cycle (C,D): Triphasic heteromorphic:
Chantransia (sporophyte) → monosporangia → **monospores** → Batrachospermum gametophyte → gametes → back to Chantransia
Distinct from Fucus/Bryopsis simple cycles.
MCQ Solution: Batrachospermum Characters A B C D
Question: Important characters: A. freshwater B. oogamous C. Chantransia D. monospore from Chantransia.
| Option | Evaluation |
|---|---|
| (A) A,B only | Incomplete—lacks life cycle |
| (B) A,B,C,D | Correct—all defining traits |
| (C) A,C,D only | Misses oogamy |
| (D) C,D only | Habitat/reproduction essential |
Answer: (B)
Taxonomic Significance
Family Batrachospermaceae diagnostic: gelatinous whorls (“beads on string”), freshwater niche, Chantransia-monospore alternation. Differs from marine red algae (no Chantransia) and Chlorophyta (isogamy). pH indicator species (acidic clean water).
Exam Strategy
Chantransia phase as key differentiator from other algae. Freshwater + oogamy narrows to Batrachospermaceae. Monospore links life cycle stages.
