Question

Assertion: Reptiles and Amphibians show metachrosis.
Reason: They have neurohormones in their skin.
A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion.
B. Both Assertion and Reason are correct and Reason is not the correct explanation for Assertion.
C. Assertion is correct but Reason is incorrect.
D. Both assertion and Reason are incorrect.

Answer 1

Hint:-Amphibian word is derived from Greek word ‘amphi’ means ‘dual’ and ‘bio’ means ‘life’, as they have ability to survive in both terrestrial and aquatic habitats. Reptile derived from Latin word which means ‘one who creeps’. The study of amphibians and reptiles is known as Herpetology, which is a branch of zoology.

Complete answer:
Amphibians and reptiles both belong to groups of vertebrates and both are ectothermic (cold-blooded), use camouflage for protection and are omnivores. Amphibians include frogs, toads, and salamanders. Almost every amphibian lays their eggs in water and in their larval or tadpole stage they live in water with gills and when they grow up into adult gills degenerate, paired lungs develop, and this feature of amphibians is said as metamorphosis. Reptiles include snakes, turtles and lizards. Reptiles lay their eggs on land as their eggs have a hard shell to prevent water loss. Reptiles have scaly skin which helps them to survive even in the hot, dry climate of deserts as scales helps them to retain moisture and protects them from predators. Metachrosis is the ability of some animals to change colour by the expansion and contraction of chromatophores (pigment-bearing cells). This feature of some animals such as chameleons helps to protect them from enemies. Colour changing signals can be neurotransmitters or hormones initiated due to changes in temperature, stress, and mood or environmental changes. Both reptiles and amphibians show metachrosis features as they have neurohormones in their skin.
Thus, the right option is A.

Note:- Amphibians are also said to be linked between the fish and the terrestrial reptiles, as amphibians are the first animals that move from sea to land. The main phenomenon behind metachrosis is the presence of a chromatophore (pigment bearing cell) inside a sac, which can reflect the light. And we can see colour change due to interaction of pigment with the light.