Question

What is the major difference between Hippocampus and Trygon?

• A. Hippocampus lived in sea water while Trygon in fresh water
• B. Trygon swims continuously, whereas Hippocampus does not
• C. Hippocampus is an Osteichthyes fish, while Trygon is a Chondrichthyes fish
• D. B & C both correct

Hint:

Remember: \[ \boxed{\text{Hippocampus} \rightarrow \text{Osteichthyes (Bony fish)}} \] \[ \boxed{\text{Trygon} \rightarrow \text{Chondrichthyes (Cartilaginous fish)}} \] Bony fishes possess a swim bladder, whereas cartilaginous fishes do not.

Answer 1

The Correct Option is D

Concept: Hippocampus (Seahorse) and Trygon (Stingray) belong to different classes of fishes.

• Hippocampus belongs to Osteichthyes (bony fishes).

• Trygon belongs to Chondrichthyes (cartilaginous fishes).
They also differ in their swimming habits.

Step 1: Identify the classification of both fishes.
Hippocampus possesses a bony endoskeleton. Therefore, \[ \boxed{\text{Hippocampus} \rightarrow \text{Osteichthyes}} \] Trygon possesses a cartilaginous endoskeleton. Hence, \[ \boxed{\text{Trygon} \rightarrow \text{Chondrichthyes}} \] Thus, Statement (C) is correct.

Step 2: Compare their mode of locomotion.
Trygon lacks a swim bladder and therefore must swim continuously to maintain movement. Hippocampus possesses a swim bladder and can remain almost stationary in water. Thus, \[ \boxed{\text{Statement (B) is also correct.}} \]

Step 3: Choose the correct option.
Since both Statements (B) and (C) are correct, \[ \boxed{\textbf{Option (D)}} \] is the correct answer.