Teeth in chondrichthyes are modified

Scales in chondrichthyes are

Read the following matches about chordates and it's characteristics. I. Petromyzon - belongs to cyclostomata and are endoparasites on some fishes. II. Scoliodon - a Chondrichthyes in which teeth are modified placoid scales. III. Hippocampus - a cartilaginous aquarium fish known as a sea horse. IV. lchthyophis is a limbless viviparous amphibian with direct development. Select the incorrect statements ?

Read the following matches about chordates and it's characteristics. I. Petromyzon - belongs to cyclostomata and are endoparasites on some fishes. II. Scoliodon - a Chondrichthyes in which teeth are modified placoid scales. III. Hippocampus - a cartilaginous aquarium fish known as a sea horse. IV. lchthyophis is a limbless viviparous amphibian with direct development. Select the incorrect statements ?

Which types of scales are found in chondrichthyes and osteichthyes?

Which types of scales are found in chondrichthyes and osteichthyes?

Chondrichthyes is characterised by

Chondrichthyes is characterised by