28. a)Why amphibians gain importance in the classification of animal
kingdom?
borocteristic features of amphibians.
Answers
Answer:
Amphibians are ectothermic, tetrapod vertebrates of the class ... Kingdom: Animalia ... Many examples of species showing transitional features have been discovered. ... These large amphibians retain several larval characteristics in their adult ...
Answer:
Amphibians, especially anurans, are economically useful in reducing the number of insects that destroy crops or transmit diseases. Frogs are exploited as food, both for local consumption and commercially for export, with thousands of tons of frog legs harvested annually.
Explanation:
The characteristics of the organisms present in class amphibia are as follows:
These can live both on land and in water.
They are ectothermic animals, found in a warm environment.
Their body is divided into head and trunk. The tail may or may not be present.
The skin is smooth and rough without any scales, but with glands that make it moist.
They have no paired fins. Unpaired fins might be present.
They have two pairs of limbs for locomotion.
They respire through the lungs and skin. Gills might be present externally in some adults.
The heart is three chambered.
The kidneys are mesonephric. The excretory material includes ammonia and urea.
They possess ten pairs of cranial nerves.
The lateral line is present during their development.
The sexes are separate and fertilization is usually external. However, in salamanders, the fertilization is internal.
Development is indirect with metamorphosis.
Breeding occurs in water. The copulatory organs are absent in males.
Eg., Frogs, Salamanders.
Also Read: Frogs