Question

The main features of the class Reptilia. How can they be described according to examples of representative species, basic morphology, skin, respiration, circulation, nitrogen waste, thermal control and types of reproduction?

Answer 1

GENERAL CHARACTERISTIC OF CLASS REPTILIA

1.repitiles are creeping and burrowing , cold blooded (ectothermic), having scales on the epideremis.commonly found in warm places.

2.Skin is dry,rough , no glands is presents and having scales and scutes.Ex- snakes and lizards

3.Respiration will carried out through Lungs, not by gills.Ribs help to expand and contract the body cavity and help for lung respiration.

4.Skull is monocondylic;i.e., having singal occipital condyle.

5.Except snake they are having 2pain of pentadactyl limbs. Each having 5 digits with claws i.e., tetrapods eithpentadactyl type

6.Heart is 3 chambered, with 2 auricales and partially divided ventricles. But in crocodilians are having 4 chambered heart. Renal portal system is less developed. RBC is nucleated.

7.Kidenys are metanephric, urinary blader may be present. Crocodiles are ammonotellic ,turtles and alligators areureotellic, lizerds and snakes areuricotelic.

8.12 pais of cranial nerves are present

9.Each ear consist of 3 parts , external middle and internal. snakes has no ears.

10.Lateral line system is absent.

11.A typical cloaca is present.

12. they are mostly oviparous .Some are ovovivioarous or viviparous type.Embryonic membrains are formed during developments.