Q.65 Which of the following statements are INCORRECT?
(A). Many animals with protostome development, undergo spiral cleavage.
(B). Flat worms exhibit, radial symmetry
(C). Ray-finned fishes are also called Sarcopterygians.
(D). Lophophore is a crown of ciliated tentacles, that function in feeding
Choose the correct answer from the options given below:
1. (A) and (D) only.
2. (B) and (C) only.
3. (B), (C) and (D) only.
4. (A) and (C) only.
Competitive exams test nuanced animal biology facts through “incorrect statement” questions. This MCQ covers embryonic cleavage, symmetry, fish classification, and feeding structures—core Animal Kingdom topics.
Correct Answer: Option 2 – (B) and (C) only
Statements (B) and (C) are incorrect; (A) and (D) are accurate.
Statement Analysis
(A) CORRECT
Many protostomes (annelids, molluscs, arthropods) show spiral cleavage where blastomeres divide obliquely around the polar axis, leading to determinate fate. Deuterostomes typically have radial cleavage.
(B) INCORRECT
Flatworms (Platyhelminthes) exhibit bilateral symmetry, not radial. Their dorsoventral flattening supports this, unlike radially symmetric cnidarians. [ from prior context]
(C) INCORRECT
Ray-finned fishes (Actinopterygii) have lepidotrichia rays; Sarcopterygians (lobe-finned fishes like coelacanths, lungfishes) have fleshy fins with bones—entirely distinct groups. [ from prior]
(D) CORRECT
Lophophore in brachiopods, bryozoans is a horseshoe/crown of ciliated tentacles trapping food via current creation. [ from prior]
Quick Comparison Table: Key Concepts
| Statement | Status | Reason |
|---|---|---|
| Protostome spiral cleavage | Correct | Classic protostome trait (e.g., molluscs) |
| Flatworms symmetry | Incorrect | Bilateral, not radial |
| Ray-finned = Sarcopterygians | Incorrect | Actinopterygii vs Sarcopterygii |
| Lophophore function | Correct | Ciliated feeding crown |
Why Other Options Are Wrong
Option 1: (A) and (D) only
Fails: Both are correct textbook facts.
Option 3: (B), (C), (D)
Fails: (D) is correct; overincludes.
Option 4: (A) and (C)
Fails: (A) is correct; misses (B).
Distractors exploit common mix-ups like symmetry terms or fish nomenclature.
Exam Tips for “Incorrect Statement” MCQs
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Verify Each: Treat as true/false first—eliminate options with correct statements.
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Mnemonics: Flatworms = “Bi-LAT-eral” (like humans); Ray-finned = “Actino-RAYS,” Lobe-finned = “Sarco-FLESH.”
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NEET Focus: Links Protostomia/Deuterostomia, phyla traits (Ch 4 Animal Kingdom).
