Which of the following are referred as non-vertebrate chordates?
Important Questions on Animal Kingdom
Which of the following statements are not true about shark?
a. The skin is tough and covered with placoid scales.
b. They possess a swim bladder which regulates buoyancy.
c. The tail of shark is heterocercal.
d. Ampulla of Lorenzini present in the snout of shark serve as thermoreceptor and electroreceptor
e. It has five pairs of gill slits covered by operculum.
What are not true?
a. Dermal scales of fishes form the exoskeleton
b. Cycloid and ctenoid scales have distinct lines of growth which aid in determining the age of the fish
c. Fish scales are never shed
d. The skin in elasmobranchs is covered with placoid scales
e. The development of a placoid scale is not like the development of a tooth
Teeth are modified ----------scales which are backwardly directed.
Choose the option that fills the blank correctly.
