Question

Which of the following represents the correct com- bination without any exception ?

Characteristics		Class
(a)	Sucking and circular mouth; jaws absent, integument without scales; paired appendages	Cyclostomata
(b)	Body covered with feathers; skin moist and glandular, fore-limbs form wings; lungs with air sacs	Aves
(c)	Mammary gland; hair on body; pinnae; two pairs of limbs	Mammalia
(d)	Mouth ventral; gills without operculum; skin with placoid scales; persistent notochord	Chondrichthyes

• A. a
• B. b
• C. c
• D. d

Answer 1

Answer: (D)

Cyclostomes do not have paired appendages. Skin in Aves is neither moist nor glandular. Only preen gland is present at the base of tail. Chondrichthyes members have gills without operculum, except Chimaera. Prototherian mammals do not have ear pinnae and aquatic mammals lack hindlimbs (like whales and dolphins).