What are the characteristics of Class Reptilia:
1. Terrestrial animals, creeping and crawling over land for locomotion. Hence the name reptilian (Latin Reptere or Reptum – to creep or crawl)
2. Body is covered by dry cornified skin also known as epidermal scales or scutes.
3. Two pairs of limbs are usually present. Tympanum represents ear.
4. Cold-blooded animals usually have three-chambered hearts. Crocodiles have a four-chambered heart
5. Snakes and lizards shed their scales as skin cast
6. Animals are dioecious and oviparous. Fertilization is internal with direct development.
7. Examples of organisms belonging to this class – Chelone (Turtle), Chameleon (Tree lizard), Crocodilus (Crocodile), poisonous snakes like Naja (Cobra), Vipera (Viper)
A. Chameleone B. Crocodilus C. Chelone D. Naja
What are the characteristics of class Aves?
1. Characteristic feature – Presence of wings. Forelimbs are modified to wings which help in flying. Most birds can fly except flightless birds like Kiwi, Ostrich, etc
2. Hind limbs generally have scales used for walking, swimming, or holding on to branches of trees.
3. Mouth is designed in the form of the beak
4. Skin is dry due to the absence of glands. However, oil glands are present at the base of the tail
5. The endoskeleton is ossified and is made of a long bone that contains hollow air cavities
6. Presence of crop and gizzard in the digestive tract of birds that helps in grinding branches, meat, and other food items
7. Four-chambered heart. Warm-blooded animals, also known as Homoiothermous i.e., are able to maintain constant body temperature.
8. Respiration is by air sacs present in the lungs
9. Birds are dioecious and oviparous. Fertilization is internal and development is direct.
10. Examples of organisms belonging to the class Aves – Nephron (Vulture), Pavo (Peacock), Struthio (Ostrich)
A. Nephron B. Struthio