By
Miha Alam
Birds:
1. They are endothermic vertebrates i.e. they maintain their body temperature.
2. Their skin is covered with feathers.
3. They have four-chambered heart to maintain high levels of energy..
4. Their bones are lightweight and usually hollow.
5. Their forelimbs are modified as wings.
6. Powerful flight muscles are attached to a large breastbone called sternum.
7. They lay eggs.
8. They can fly and have beaks made out of protein called Keratin.
9. The respiratory system consists of lungs and anterior and posterior air sacs. This helps to supply oxygenated air to the lungs when it inhales as well as when it exhales.
10. The digestive system is adapted for dealing with large quantities of food that must be eaten to maintain high level of energy.
11. They have no teeth. They swallow small stones that help them to grind their food in the gizzard (part of digestive system).
12 The legs are made up of skin, bone and tendons and feet are adapted to perching, swimming walking and catching prey.
Fishes
1. Ectothermic vertebrates
2. They have paired fins used for locomotion.
3. No movable eyelids and no tear glands.
4. Have the inner ear but don’t have a cochlea.
5. Lack internal nostril
6. They breathe using gills
7. They have two chambered heart. Non divided atrium and ventricle in the heart
8. They reproduce sexually and all fishes have separate sexes.
9. Reproduction in fishes is called Spawning.
10. Excretes nitrogenous waste
11. They have highly developed sensory systems. The lateral line system is a line of fluid filled canals running along the sides of a fish that enable it to detect movement and vibrations in the water.
12. Most fishes have scales which helps them to move in water with out friction.
13. Swimbladder- Gas pressure in the swimbladder alters the specific gravity of the whole body, which enables the fish to float in the water.
Amphibians:
1. Ectothermic i.e. their body temperature changes according to the environmental temperature.
2. They undergo metamorphosis. Fertilized eggs-tadpoles-adults.
3. They have three- chambered heart to maintain high level of energy used for walking.
4. They have large protruding eyes at the top of the head- an adaptation that enables them to stay submerged in the water with only their eyes above the surface.
5. Slightly cornified epidermis
6. Large mucous glands abundant
7. Movable eyelids and tear glands protect and clean the eye
8. Have muscular tongue which is long and sticky which helps them to catch their prey quickly.
9. Mating calls-Male frogs use sound to attract the females with females also having distinct calls to indicate whether they are willing to mate.
10. Larval external gills are lost at metamorphosis
11. Separated atriums in the heart
12. The hind legs are muscular and powerful for jumping.
13. Tympanic membrane- Vibrations from water or air are picked up by Tympanic membrane and transmitted to the inner ear and then to the brain.
Reptiles:
1. Ectothermic
2. They have a dry, thick skin covered with scales which prevents the loss of body moisture and provides additional protection from predators.
3. Most of them have three chambered hearts but some have four chambers e.g crocodiles.
4. No Cutaneous glands
5. Scent glands present
6. Long trunk ribs
7. Tympanic membrane
8. Large lungs
9. They reproduce by laying eggs on land. The amniotic egg was the adaptation that made reptiles become independent from water.
10. The amniotic egg provides nourishment to the embryo and contains membranes that protect it from the terrestrial environment.
11. They have claws that help them to catch the prey and protect themselves.
12. The positioning of legs under the body rather than at right angles provides greater support and makes walking and running easier.
Mammals:
1. Endothermic vertebrates i.e. they can maintain their body temperature.
2. They take greater care of the young ones
3. Body covered with hair
4. The females possess mammary glands
5. They have large number of glands like sweat glands, oil glands and scent glands
6. They have different types of teeth adapted to the type of food.
7. They have modified limbs adapted for a variety of food gathering.
8. They have higher learning skills.
9. They have a high level of metabolism and need high level of energy for which they have a diaphragm which is a muscle that helps to expand the chest cavity to take in large amounts of oxygen.
10. They have a four chambered heart which helps to maintain high rate of metabolism.
