Hi, today we are going discuss the characteristics and classification of amphibia and other details. Amphibians are under the kingdom animalia and phylum chordata consisting of around 3000 species. They are cold blooded vertebrates with both land and water habitat so they are known as amphibia.
Table of Contents
General Characteristics of Amphibia:
Now we will discuss all the general characteristics for the members of class amphibia which help us to distinguish them from another organism.
Why Are They Known As Amphibians ?
Members of class amphibia can live on land but a portion of their life cycle they need water to complete their life cycle so they are known as amphibia ( amphi means dual so amphibia related to dual life).
Amphibians Are Ectothermic Animal:
Amphibians are cold blooded vertebrates unable to maintain internal body temperature constant their body temperature vary with the external environment so they are poikilothermic or ectothermic.
Division of Body:
The whole body of an amphibian can be divided into two parts: head and trunk, tail present in tadpoles but absent in the natural stage.
Skin Are Adapted For Respiration:
They use their skin as a respiratory surface for gaseous exchange and for this reason their skin is moist, without any scale. The glands present on their skin make their skin moist which is suitable for gaseous exchange through the skin.
Limb System:
They do not have paired fin unpaired fin may present they have two pairs of limbs for locomotion.
Respiratory Organ in Amphibia:
Amphibians respire through lungs and skin but some adult amphibians have gills for respiration while most of them have gills in the larva phase.
Three Chambered Heart:
Amphibian heat is there chambered two auricles and one ventricle which cause mixing of oxygenated and non oxygenated blood in their heart.
Excretory Organ of Amphibia:
Major excretory product for land amphibians is urea while a major excretory product for aquatic amphibians is ammonia and their excretory organ is mesonephric kidney.
Ten Pairs of Cranial Nerve:
Amphibians have ten pairs of cranial nerves while other advanced animals process more than ten pairs of cranial nerves.
Lateral Line Absent in Adult Amphibia:
Adult amphibians do not process lateral lines but in the larva stage some amphibians have lateral lines which is useful to sense different parameters in water like temperature, presence of any harmful chemicals.
Fertilization is External in Amphibians:
Male and female are separate in amphibia and their fertilization occurs externally in water. Fertilization occurs in water because their eggs do not have a hard shell for protection but in salamanders fertilization is internal.
Development is Indirect in Amphibia:
Their development is not direct; they pass through different larval stages before becoming fully matured.
Breeding in Amphibia:
Their breeding needs water so they prefer to copulate during the rainy season and male amphibians do not have male copulatory organs.
Classification of Amphibia:
Class amphibia can be divided into three orders depending upon various characteristics – order apoda, order urodela, order anura which we will discuss below one by one.
Order Apoda General Characteristics:
Apoda are Without Legs:
The term ‘apoda’ means they do not have any limbs unlike other members of amphibia and their body is covered by scale.
Apoda Are Known As Blind Worms:
It is a very peculiar character of order apoda that they do not have open eyes because their eyes are covered by skin or bone which makes them famous as ‘blind worms’.
Apoda Have Head With Tentacles:
Their heads have some tentacles like structure which enables them to sense underground prey which helps them to find their food easily.
Apoda Are Venomous:
Presence venom glands make this order of amphibia venomous.
Order Urodela:
Urodela Have Tail:
Members of order Urodela have tails which are absent in most of the other amphibians in the adult stage.
Urodela Have Limbs:
Unlike Apoda this order has four equally sized limbs for locomotion.
Order Anura:
They have four limbs among which front two are modified for jumping, their head is fused with trunk, tail is only present in the larva stage but absent in the adult phase.
Reference: Characteristics and Classification of Amphibia
Read More: Alimentary Canal of Cockroach
Hi Everyone!!! Welcome to Imaluop. Imaluop always try to learn some new and he want to share to other people. Here we will try to learn various topics on Science, specially on Biological Sciences.
