Reptiles Class 4 Notes Science

Reptiles:
Reptiles are cold blooded animals having dry skin covered with scales, found everywhere except in cold places. Reptiles warm themselves in the sun shine to be active. Reptiles are air breathing animals, though many live not only on land but also in water. They have tungs for breathing. Some water reptiles absorb oxygen in water through membrane in their mouth. 

Alligators and Crocodiles

Alligators and crocodiles are larger in size. They have webbed feet to walk on the land and long tail to swim in water- They are hunters with huge and lot of sharp teeth to tear their prey. Tails are long and powerful to swim in water. An alligator has a shorter snout than a crocodile.

Alligator has a shorter snout

Crocodile teeth stick out when its mouth is closed  

Lizard’s
3,000 species of lizard are there on the earth. They have four legs and a long tail. On getting unfavorable condition, they shed their tail which is again regenerated. Gila monster and Mexican beaded lizard are poisonous-

Garden lizards are found near our houses, in the garden etc. 

Komodo dragon is the largest lizard  

 Snakes
Approximately 2,500 species of snake are there on the earth. They are found everywhere, except in Antarctica. Viper is the most dangerous snake. Its poison can kill a human being. Python and boa can coil around prey and squeeze it to death. It can swallow prey larger than its size.

Reticulated python is the world largest snake Snakes don't have limbs and move by slithering around the ground. Snakes shed their skin if damaged and worn out. This process is called molting. Many species of snakes are found in sea. Black mamba is the fastest snake which lives in Africa. Its speed is 11 km/h. Snakes have teeth but not for the chewing and hence it swallows its prey. 
Snake undergoing molting process  Turtles and Tortoises
Tortoises are very slow moving reptiles. Tortoise lives on land and turtles live in water. They have the life span of about 150 years.

The leather back is the largest of all turtle 

Feeding in Reptiles
Alligators and Crocodiles are carnivorous. They eat birds, giraffes, insects, spider or anything that comes in their way. Turtles eat aquatic creatures like snails, shrimps, sea grass and jelly fish etc.
All snakes are carnivorous that they feed on other animals.

Adaptation in Reptiles 

Chameleon is a type of lizard that can change its colour to escape from the predators or to get near to its prey. Chameleon becomes dark in colour in winter and lighter in hot condition. This process is called as camouflage.
Regeneration: Lizards looses its tail to escape from predator or unfavorable condition. The broken tail is regenerated again.
Molting: Snakes shed their skin if damaged and worn out. This helps in proper growth.
Hibernation: Snakes and lizards undergo hibernation process to avoid extreme cold. They again come out from their burrows in summer.

Reproduction in Reptiles
Reptiles lay eggs in warm dry places. The heat of Sun helps in hatching the eggs. Sea turtle lay eggs on the land. They take them to water after hatching.

Turtle come on land to lay their eggs 

Life cycle of reptile:

Commonly Asked Questions:

Consider the following statements:
Statement A: Alligators and Crocodiles are fishes because they live in water.
Statement B: Alligator and Crocodiles are reptiles because their dry body is covered with scales and are cold - blooded.
Which one of the following is correct about the above statements?
(a) Statement A is true
(b) Statement B is true
(c) Both A and Bare true
(d) Both A and B are false
(e) None of these
Answer : (b)
Explanation 
Living in water doesn't mean that the organism is fish. Alligators and crocodiles possess dry skin covered with scales. Reptiles are cold blooded.
Therefore, option (B) is correct and rest of the options is incorrect.
Boa and python are the names of which one of the following species?
(a) Lizards
(b) Crocodile
(c) Snake
(d) Cartilaginous food
(e) All of these
Answer: (C)
Explanation
Boa and Python are non-poisonous snakes but they can kill their pray by crushing their body. Therefore, option (C) is correct and rest of the Options is incorrect..