Animal Kingdom

               Phylum – Chordata

 

3 characteristic features –

                                               1.Notochord

                                               2.Dorsal hollow nerve chord

                                                3.Pharyngal gill pores

Other features – Organ system level organization, bilaterally symmetrical, Triploblastic, Coelomates, Closed blood circulation system.

Phylum Chordata is divided in 3 subphyla –     I. Urochordate        

                                                                                  II. Cephalochordate   

                                                                                  III. Vertebrata

Only larval Urochordates have notochord in their tails, while Cephalochordates have notochord from head to tail.

Examples – Urochordates – Ascidia, Salpa, Doliolum

                     Cephalochordates – Amphioxus

In vertebrates Notochord converts in spinal-cord, as they grow in adult. It is called that all Vertebrates Are Chordates, but all chordates are not Vertebrates. Vertebrates have a 2,3 or 4 chambered heart at ventral side.

Vertebrates are divided in 7 classes, which classes included in Agnathostomata or Gnathostomata. Classes are here

1.       1.Cyclostomata – all animals of this class are parasites on fishes. Their body is long, which includes 6-15 pairs of gill pores. Their mouth is round and jawless. Lack of scale and coupled wings. Head and spinal cord is cartilaginous. Closed blood circulation system. Cyclostomates live in sea but for reproduction they need sweet water. They died after some days of reproduction. After formation larva comes to sea again. larval stage – Amocite

Examples – Petromyzon, Mixine(hag fish)

2.       2.Chondrichthyes – The Cartilaginous fishes. These are residence of marine water(sea). Their endoskeleton is made up of cartilage. They have mouth on ventral side. Gill pores are not covered by Operculum. Skin is rough and placoid scales are present on skin. Their jaws are very powerful. Heart has 2 chambers, which contains one arteriole and one ventricle. Some of them has electric organs as Torpedo and some has venom as Trigon. Oviparous or Ovoviviparous. Examples – Dog fish (Scoliodon), Pristis, Trigon, big white shark.

3.       3.Osteichthyes – The Bony fishes. It is found in all types of water residents. Mouth found in the end of starting point. 4 pairs of gill pores found and covered both sides by Operculum. Skin is covered by cycloid, teinoid, ganoid scales. It’s shaped like spindle. Swim bladder is present. Heart has 2 chambers one arteriole and one ventricle. Oviparous.

              Examples – Flying fish, sea horse, Rohu, Katla, Fighting fish, Petropisum.

4.       4.Amphibia – Skin moisturized, scales are absent, Poikilothermic. Respiration – by gill pores or skin. Heart – 3 chambered two arterioles and one ventricle. Larval stage present and formation direct.

        Examples – Buffo, Rana tigrina, hila, Salamander, Ichthiophis.

5.       5.Reptilia – 2 pairs of foot are present. Heart 3 chambered (exception – Crocodile [4 chambered heart]). Rough skin has extra skinner scutes/scales. Mostly Ureotelic some exceptions as crocodile is ammonotelic.  

Examples – Crocodile, Alligators, Turtles, Chameleon.

6.        6.Aves – wings are present and flying ability is also present exception – Ostrich. Front foot make wings. No skin glands present except tail’s oil gland. Endoskeleton’s bones are hollow and Air sacs are present. Digestion helping structure crop present. Heart 4 chambered. Animals are homoeothermic. Respiration by Pulmonary sacs. Air sacs are helping respiratory organs. Long bones are pneumatic.

       Examples – crow, parrot, Ostrich, peacock, Penguin, Colombo.

7.       7.Mammalia – Milk producing glands present, which feed the young child. Hairs are present on skin. 2 pairs of foots are present. Various types of tooth. Heart 4 chambered two arterioles and two ventricles. Respiration by diaphragm. Mostly viviparous exception Monotremes. Optic lobes divided in 4 lobes which called Corpora Quardigamina. A relation between mother and child (embryo) present which called placenta.

        Examples – Platypus (Oviparous), kangaroo, flying fox, camel, monkey, rat, dog, cat, elephant, horse, dolphin, blue whale, tiger, lion, human.