Diversity in Living Organisms

Phylum 10 Vertebrata

• These Animals have vertebral column.
• Ventral heart, with dorsal and ventral blood vessel and closed blood vascular system.
• They have Complete digestive system.
• A cartilaginous or bony endoskeleton present in majority of members.
• Possess notochord.

Class 1. Pisces

• Animals belonging to this class have streamlined body which is either laterally compressed or spindle-shaped or dorsoventrally flattened and disc shaped.
• Their skin is tough and covered with scales.
• Respiration is carried out through gills.
• They have fins for locomotion.
• Muscular tail is used for movement.
• Their heart is two chambered.
• Examples- Sharks, Rays, Lampreys, etc

Class 2. Amphibia

• These animals live partly in fresh water and partly on land
• Their skin is smooth or rough, moist, slimy, glandular and mostly without scales.
• Body of the amphibians includes a distinct head and trunk and has no neck.
• Two pairs of pentadactyl (five digit) limbs are present. Digits or toes are without claws.
• Three-chambered heart has two auricles and one ventricle.
• Respiration is carried out either by gills, lungs, skin.
• They are Oviparous and cold blooded animals
• Examples – Rana catesbeiana (bull frog), Hyla cinerea (tree-frog)

Class 3. Reptila

• They are Ectothermic or cold-blooded, terrestrial or aquatic vertebrates a body covered with dry.
• Body of reptiles varies in form and is usually divided into head, neck, trunk and tail.
• Limbs with clawed digits are present.
• Respiration is carried out through lungs only.
• Heart is three chambered and is divided into two auricles and an incompletely divided ventricle.
• Examples: Testudo (land-tortoise), Uromastix (sand-lizard), Hemidactylus (house wall-lizard), Draco (flying-lizard), chamaeleon.

Class 4. Aves

• These are warm-blooded with various flight adaptations.
• Feathers cover most of their body.
• Fore-limbs are modified into wings for flight.
• Hind-limbs bear four clawed digits.
• Narrow jaws form a horny break.
• Bones of endoskeleton are light and spongy due to the presence of air cavities
• Respiration is carried out through lungs.
• Four-chambered heart with two auricles and two ventricles present.
• Examples – Parrot, Owl, Eagle, etc

Class 5. Mammalia

• Mammals are warm-blooded (endothermic and homeothermic) and the most evolved animals of animal Kingdom.
• Hair and the subcutaneous fat form an insulating layer. Sweat glands, scent glands and (oil) glands are present.
• Their body is divisible into head, neck, trunk and tail. Movable eyelids are present.
• Females have milk-producing mammary glands which secrete milk for the nourishment of the young.
• Fleshy external ears (pinnae) are present.
• Two pairs of limbs are present with five digits of claws, nails or hoofs.
• A muscular diaphragm is present which separates thoracic and abdominal cavities.
• Respiration is carried out through lungs only.
• Heart is four-chambered.
• They are Viviparous.
• Examples: Macropus (Kangaroo), Rattus (rat), Felis (cat), Macaca (monkey), Homo (Human beings).