Which has no skeleton ?

Which of following has no skeleton ?

Give the answer of following questions by observatios from given figures: (i). Which fish has air bladder? (ii) which fish is known as saw fish? (iii) which fish is cartilaginous fish? (iv). Which animal is ectoparasite on true fishes? (v) Which fish has paired fins? (vi) which fishh has body skeleton? (vii) Which fish has 4-pairs of gills? (viii) Whch fis has operculum? (ix) Which fishes are viviparous? (x) Which fish lives in fresh water?

Give the answer of following questions by observatios from given figures: (i). Which fish has air bladder? (ii) which fish is known as saw fish? (iii) which fish is cartilaginous fish? (iv). Which animal is ectoparasite on true fishes? (v) Which fish has paired fins? (vi) which fishh has body skeleton? (vii) Which fish has 4-pairs of gills? (viii) Whch fis has operculum? (ix) Which fishes are viviparous? (x) Which fish lives in fresh water?

What is skeleton?

Earthworm has no skeleton but during burrowing, the anterior end becomes turgid and acts as a hydraulic skeleton. It is due to

Earthworm has no skeleton but during burrowing, the anterior end becomes turgid and acts as a hydraulic skeleton. It is due to

Which animal has an outer skeleton?