Regarding reproduction in Cyclostomes:
I: They are marine but migrate for spawning to fresh water.
II: After spawning, within a few days, they die. 
III: Their larvae, after metamorphosis, return to the ocean.
1. Only II is correct
2. Only I and II are correct
3. Only II and III are correct
4. I, II and III are correct

Subtopic:  General Introduction: Vertebrates & Agnatha |
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Chondrichthyes:
1. are marine animals and have cartilaginous endoskeleton
2. have a mouth located dorsally
3. have teeth that are modified cycloid or ctenoid scales directed backwardly
4. have the capacity to regulate their body temperature
Subtopic:  Comparative study of Cartilagenous & Bony Fishes |
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What would not be true regarding cartilaginous fishes?
1. In males, pelvic fins bear claspers
2. Some of them have electric organs [Torpedo]
3. None of them is viviparous
4. Some possess poison sting [Trygon]
Subtopic:  Comparative study of Cartilagenous & Bony Fishes |
 88%
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Identify the incorrect statement regarding bony fishes:
I: They have four pairs of gills which are covered by an operculum on each side.
II: Due to the absence of air bladder, they have to swim constantly to avoid sinking.
III: Skin is covered with placoid scales.
IV: Mouth is mostly terminal.
 
1. Only II 2. Only II and III
3. Only I and IV 4. Only IV
Subtopic:  Comparative study of Cartilagenous & Bony Fishes |
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Which of the following is not a characteristic of Amphibians?
1. Most have two pairs of limbs and tail is present in some.
2. Alimentary canal, urinary and reproductive tracts open into a common chamber called cloaca which opens to the exterior.
3. Respiration is by gills, lungs and through skin.
4. The heart is two chambered with one atrium and one ventricle.
Subtopic:  Study of Amphibians |
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In reptiles:
I: Body is covered by dry and cornified skin, dermal scales or scutes.
II: External ear is not present and tympanum represents the ear.
III: Scales are shed as skin cast in all members.
IV: Fertilization is internal and development is direct.
 
1. Only II is correct 2. Only II and IV are correct
3. All are correct 4. Only I and II are incorrect
Subtopic:  Study of Reptilia |
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Which of the following reptiles has a four chambered heart?
1. Crocodile 2. Wall lizard
3. Turtle 4. Tortoise
Subtopic:  Study of Reptilia |
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In birds:

a: the characteristic feature is the presence of feathers.
b: forelimbs are modified into wings.
c: flight is present in all members.
d: hind limbs do not have scales.

1. Only (a) and (d) are incorrect
2. Only (c) and (d) are correct
3. (a), (b) and (c) are correct
4. Only (a) and (b) are correct

Subtopic:  Study of Aves & Mammals |
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Birds are not characterized by:
1. a fully ossified endoskeleton
2. pneumatic long bones
3. absence of crop and gizzard in the digestive tract
4. a dry skin without glands except the oil gland

Subtopic:  Study of Aves & Mammals |
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Consider the given two statements:

I: Birds have a four chambered heart and are warm blooded.
II: Respiration in birds is by lungs that are connected to air sacs.
1. I is correct but II is incorrect
2. Both I and II are correct.
3. Both I and II are incorrect.
4. I is incorrect but II is correct.
Subtopic:  Study of Aves & Mammals |
 89%
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