Question

Which of the following classes is incorrectly matched with its general characters?

• A. Cyclostomata: Lack jaws and paired fins and body is covered with placoid scales
• B. Osteichthyes: Four pairs of gills are covered with an operculum and skin is covered with cycloid scales
• C. Reptilia: Tympanum represents ear and fertilisation is internal
• D. Aves: Endoskeleton is fully ossified, and long bones are hollow with air cavities called as pneumatic bones

Answer 1

The correct option is A Cyclostomata: Lack jaws and paired fins and body is covered with placoid scales

Cyclostomata is a group of chordates that includes jawless fishes. They have an elongated body and have 5-16 pairs of gills. They do not have scales on their body. The skin is soft, smooth and contains unicellular mucous glands.