Question

An oviparous and carnivorous fish with placoid scaled

Answer 1

The members of the Class Chondrichthyes contains placoid scales.

Some characters of the members of this class includes :

1. The members of this class has endoskeleton that is of cartilaginous type.

2. Their mouth is situated in ventral position.

3. They have a notochord which exists throughout their whole life.

4. They have gill slits that are without gill cover or operculum.

5. Their skin contains minute or small type of scales called placoid scales.

Answer 2

Placoid scaled of Fish  

Explanation:

• A fish scale is a little inflexible plate that becomes out of the skin of a fish.
• The placoid sizes of cartilaginous fishes are additionally called dermal denticles and are fundamentally homologous with vertebrate teeth.  
• Jaws, combined limbs, profound instinctive curves alongside the pharynx, an inward ear containing 3 crescent channels, a matched nasal depression. Very much created electroreceptors.  
• Cartilaginous endoskeleton. Skin secured by placoid scales and mucous organs. Teeth are altered placoid scales.  
• No lungs or swim bladder the bouyancy is kept up primarily by huge stores of liver oil.  
• Caudal balance is heterocercal. (a tail with an upper flap).  
• Seperate genders, interior preparation and direct development.