Given below are two statements: 
Assertion (A): Echinoderms possess an endoskeleton of calcareous ossicles.
Reason (R): These organisms are marine or freshwater dwellings.
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.
 

 

Subtopic:  Phylum Echinodermata |
 69%
Level 2: 60%+
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Consider the given two statements:
Assertion (A): Balanoglossus possess external fertilization.
Reason(R): Saccoglossus undergo direct development during their life cycle.
 
1. Both (A) and (R) are True and (R) correctly explains (A)
2. Both (A) and (R) are True and (R) does not correctly explain (A)
3. (A) is True, (R) is False
4. (A) is False, (R) is False
 
 
 
Subtopic:  Phylum Hemichordata |
 67%
Level 2: 60%+
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Assertion (A): Aschelminths and Annelids possess bilateral symmetry.
Reason (R): Both Aschelminths and Annelids are coelomates
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.

 
 
 
Subtopic:  Phylum Annelida | Phylum Arthropoda |
 80%
Level 1: 80%+
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Assertion (A): Choanocytes or collar cells line the spongocoel and the canals in poriferans.
Reason (R): Poriferans possess spicules and spongin fibres.
 
1. Both (A) and (R) are True and (R) is the correct explanation of (A).
2. Both (A) and (R) are True but (R) is not the correct explanation of (A).
3. (A) is True but (R) is False.
4. Both (A) and (R) are False.
Subtopic:  Phylum Porifera |
 82%
Level 1: 80%+
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Assertion (A): All vertebrates are chordates but all the chordates are not vertebrates.
Reason (R): All the vertebrates are characterised by the presence of a notochord, a dorsal hollow nerve cord and paired pharyngeal gill slits at some stages of the life cycle.
 
1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. (A) is true but (R) is false.
4. Both (A) and (R) are false.

 
Subtopic:  General Introduction: Vertebrates & Agnatha |
 51%
Level 3: 35%-60%
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Choose the correct statement
1. Metamerism first developed in Arthropoda
2. Triploblastic animals lacking coelom are platyhelminths and annelids
3. Coelomate animals in which blastopore forms anus are grouped under deuterostomes
4. Coelom is the body cavity found between ectoderm and outer body wall

 
Subtopic:  Phylum Arthropoda |
 67%
Level 2: 60%+
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Read the following statements:
i. Longitudinal and circular muscles exist
ii. Body wall remains covered by the glandular epidermis
iii. Metamerism present
iv. Closed blood vascular system
The above statements exemplify which organism?
1. Flatworm
2. Ophiura
3. Wuchereria
4. Earthworm
 
Subtopic:  Phylum Annelida |
 86%
Level 1: 80%+
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Which of the following is correct?
 
1. Archaeopteryx is thought to be the transitional fossil between dinosaurs and birds since, like birds Archaeopteryx had feathers and a fused collar-bone indicating the flying ability
2. Cloaca is present in Balenoptera
3. In Physalia, digestion is first extracellular and then intracellular digestion occurs
4. Both (1) and (3)
Subtopic:  Study of Aves & Mammals |
 82%
Level 1: 80%+
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Choose the correct match:
 
1. Branchostoma : Notochord persist through out the life
2. Ascidia : Notochord present in larva and disappears in adult
3. Doliolum : Notochord present in the larval tail only
4. More than one option is correct 
Subtopic:  Phylum Hemichordata | General Introduction: Vertebrates & Agnatha | Class Cyclostomata |
 82%
Level 1: 80%+
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Lampreys:
1. May or may not possess jaw
2. Is included in the division Agnatha where notochord is present only in the early stages
3. Possess an elongated body with gill slits for respiration
4. Are devoid of scales and possess paired fins

 
Subtopic:  General Introduction: Vertebrates & Agnatha | Class Cyclostomata |
 51%
Level 3: 35%-60%
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