NTA Abhyas NEET2020BotanyAnimal KingdomPractice
Read the characteristics given below of a chordate: a) two-chambered heart b) poikilotherms c) exclusively marine d) oviparous with direct development e) separate sexes Which of the following possess all of the above features?
Options
- ALabeo
- BRana
- CTrygon
- DExcoetus
Correct answer
D. Excoetus
Step-by-step solution
Class Osteichthyes: It includes both marine and fresh water fishes with bony endoskeleton. Their body is streamlined. Mouth is mostly terminal.. They have four pairs of gills which are covered by an operculum on each side. Skin is covered with cycloid/ctenoid scales. Air bladder is present which regulates buoyancy. Heart is twochambered (one auricle and one ventricle). They are cold-blooded animals. Sexes are separate. Fertilisation is usually external. They are mostly oviparous and development is direct. Examples: