nostrils
mouth
gill slits
swimming bladder
B. mouth
a rounded body with ventral gill clefts
a flattened body with dorsal gill clefts
a flattened body with ventral gill clefts
any of these
sawfish
seahorse
electric ray
sucker fish
teleosts
sharks
lung fishes
rays
a shell
egg case of skate fishes
a colony of skate fishes
none of these
lungs
air bladders
cartilaginous skeleton
fins
Coelocanth
Diodon
Sturgeon
Labeo
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
Sharks
Stingray
Dogfish
Catfish
Osteichthyes
Chondrichthyes
Dipnoi
Holocephali
hippocampus
labeo
anabes
none of these
vitamin A
iron
calcium
vitamin B complex
sound production
respiratory
locomotion
hydrostatic
anandromous migration
catadromous migration
cartilaginous fish
none of these
live at the bottom of rivers
live in shallow streams
are active swimmers
live in sea water
Primates
Aves
Crocodiles
Pisces
Five pairs of gills covered with operculum
Homocercal tail
Eight pairs of gills
Any of these
Shark
Cod
Amia
Both (a) and (b)
10 volts
100 volts
50 volts
150 volts
Trygon
Torpedo
Chimaera
Sphynta
Saurology
Traumatology
Torpedology
Ichthyology
the nature of their scales
the position of the mouth
the position of gill slits
the kind of the tail fin
dog fish
bony fishes
both (a) and (b)
all fishes
cartilaginous fishes
bony fishes
both (a) and (b)
all fishes except sharks
Placoid scales
Ventral mouth
Operculum
Five pairs of gill slits
having gills not covered by operculum
presence of lateral line system
presence of large scales
presence of terminal mouth
cat fish
dog fish
flying fish
seahorse
pharyngeal gills
paired fins
dermal scales
all of these
olfactoreceptors
rheoreceptors
gustoreceptors
chemoreceptors
placoid
cycloid
ctenoid
rhombiod
Oxygen
Carbon dioxide
Fish food
Decoration