NEET2012BotanyAnimal KingdomActual
Which one of the following categories of animals, is correctly described with no single exception in it?
Options
- AAll reptiles possess scales, have a threechambered heart and are cold-blooded (poikilothermal)
- BAll bony fishes have four pairs of gills and an operculum on each side
- CAll sponges are marine and have collared cells
- DAll mammals are viviparous and possess diaphragm for breathing
Correct answer
B. All bony fishes have four pairs of gills and an operculum on each side
Step-by-step solution
Prototherian mammals are oviparous. Sponges are aquatic mostly marine some freshwater have cellular grade of organization. Choanocytes or collar cells are characteristics of porifers. Four pairs of gills occur in bony fishes. The gills are covered over by operculum on either side. All reptiles posses scales, are cold blood but have three-chambered and four-chambered heart.