Endoderm
Mesoderm
Ectoderm
Integument
B. Mesoderm
sharks
whales
lung fishes
rays
10 volts
100 volts
50 volts
150 volts
respiration
sound production
excretion
movement
placoid
cycloid
ctenoid
rhombiod
lungs
air bladders
cartilaginous skeleton
fins
Shark
Cod
Amia
Both (a) and (b)
sawfish
seahorse
electric ray
sucker fish
a rounded body with ventral gill clefts
a flattened body with dorsal gill clefts
a flattened body with ventral gill clefts
any of these
anterior fins
ray fins
pectoral fins
paired fins
Dipnoi
Osteichthyes
Cyclostomata
Chondrichthyes
Five pairs of gills covered with operculum
Homocercal tail
Eight pairs of gills
Any of these
electric fish
saw fish
stone fish
dog fish
Placoid scales
Heterocercal tail fin
Ventrally placed mouth
Operculum
live at the bottom of rivers
live in shallow streams
are active swimmers
live in sea water
live in sea water and migrate to fresh water rivers and lakes for breeding
live in fresh water and migrate to sea for breeding
both (a) and (b)
none of these
dorsal
ventral
caudal
pelvic
a shell
egg case of skate fishes
a colony of skate fishes
none of these
Whale
Tadpole
Aquatic urodeles
Common Indian dog fish
cartilaginous fishes
bony fishes
lung fishes
paleontological fishes
Primates
Aves
Crocodiles
Pisces
nostrils
mouth
gill slits
swimming bladder
Endoderm
Mesoderm
Ectoderm
Integument
pelvic fins
cloacal fins
anal fins
caudal fins
Placoid scales
Ventral mouth
Operculum
Five pairs of gill slits
Osteichthyes
Chondrichthyes
Dipnoi
Holocephali
the nature of their scales
the position of the mouth
the position of gill slits
the kind of the tail fin
having gills not covered by operculum
presence of lateral line system
presence of large scales
presence of terminal mouth
mollusc
mammal
star fish
bony fish
Dasyatis
Chimaera
Sphyma
Torpedo
pharyngeal gills
paired fins
dermal scales
all of these