Amphibian include anurans, urodelans and apodans. In all these groups of amphibians we come across with a great deal of parental care. Amphibians show several mechanisms to protect their eggs…
Neoteny is defined as the failure or delay of larva to metamorphose while becoming sexually mature. It is character of some amphibians.   The best example is axolotl larva of…
Based on characters of amphibians the present day (extant) amphibians are classified Into 3 orders.   Order 1. Anura - (Frogs and Toads) Order 2. Urodela - (Salamanders) Order 3.…
Amphibians are cold blooded vertebrates. In the Devonian period of palaeozoic era they were originated from fishes, in the carboniferous period, they increased their number, hence that period is called…
Amphibians are the earliest tetrapods. They were descended from fish like ancestors. They were developed in the Devonian period. They flourished during carboniferous period. It is called “Age of Amphibians”.…
On the upper and lower surfaces of the head a number of tin- branched structures are present. They are called ampullae of lorenzini. Each ampulla contains two parts.   Expanded…
It lies in the auditory capsule of the skull. It is useful for maintenance of equilibrium. In the fish external and middle ears are absent. Internal eats covered by cartilaginous…
In male shark claspers are present. The claspers are rod like copulatory organs present on the inner borders of the pelvic fins. They are supported by carfilages. Each clasper has…
In Scoliodon the olfactory lobes are olfactory organs or nasal sacs.   They are present in the olfactory sacs of cranium. They develop from the ectoderm. They open out through…
On the lateral sides of think and tall lateral line canals are present. They are present deeply In the dermis. In the head region there are connected by transverse canals.…

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