Class aves centrum

1. Gallus domestica Class Aves

2. CLASSIFICATION Kingdom: Animalia Phylum: Chordata Class: Aves Order: Galliformes Family: Phasianidae Subfamily: Phasianinae Genus: Gallus Species: Gallus gallus Subspecies: G . g. domestica

3. Gallus gallus domestica

4. External parts of the chicken

5. Chicken eyes and nostrils Eyes attached are also much bigger than in mammals such as humans . Orbits are made of many small bones that merged together. They made a thin plate. Nostrils Located at the end of the beak

6. eyelids Chickens have 3 eyelids: upper eyelid Lower eyelid Nictitating membrane

7. Nictitating membrane  transparent or  translucent  third  eyelid can be drawn across the  eye for protection and to moisten it while maintaining visibility to protect the parents' eyes from their chicks while they are feeding them

8. Beaks and ear openings Have a pointy beak for picking up food No teeth are present Located at the sides of their head behind the eyes covered by feathers are more like ear holes No outer ear, or pinna They have visible ear lobes

9. It is believed that the same gene that determines the color of the ear lobe also determines egg color . Their ear lobes also can be colored from near white to near black. These birds will lay eggs that are nearly white to a deep, soft brown. The shade of brown of the egg will be indicated by the degree of color of the ear lobe. In other words, a chicken with blackish lobes will not lay a black egg, but it may be a deep brown.

10. wattle Wattles are located under the chin. They are meaty, red growths . Both male and female chicken have wattles. wattles cools down the chicken. This happens when the blood circulates from the comb to the wattles. The circulating blood lowers the temperature of the chicken during the hot weather.

11. comb fleshy protuberance on top of the head of a chicken the cockerel have a larger comb than the hen chicken act as a cooling mechanism for the birds large combs on males attract females as chickens can detect colour and are very attracted to the colour red . serves as an indicator of the bird’s health.

12. Types of combs

13. The Forelimb

14. The Forelimb The bird’s wing and is responsible for powered flight. Primarily supported by an elongated radius, ulna, and modified wrist bones.

15. The Forelimb

16. The Forelimb Upper Arm Short and stout humerus Connects the scapula with the lower arm (or forearm) Provides the musculature necessary for flight

17. The Forelimb

18. The Forelimb Forearm Composed of an elongated  radius and  ulna Serves as attachment point for flight feathers Reduced wrist flexion

19. The Forelimb

20. The Forelimb Manus The phalanges of the bird wing follow a trend of reduction and fusion to form the distal part of the wing Modern birds have mostly only the second digit of the hand present

21. The Forelimb

22. The Hindlimb

23. The Hindlimb Composed of the thingh, shank and foot. Enables bipedal locomotion for birds.

24. The Hindlimb Thigh Upper portion of a bird’s hindlimb Composed of a short femur.

25. The Hindlimb

26. The Hindlimb Shank Lower portion of a bird’s hindlimb Composed of the tibiotarsus (fused tarsus and proximal part of the tibia).

27. The Hindlimb

28. Foot and remiges

29. FOOT Hallux or hind toes Inner toe Middle toe Outer toe Scales Reticulate scales

30. Remiges

31. Pterylae

32. Region on the chicken skin where feathers grow Symmetrical tracts Separated from each other by semi- apteria Feather macropattern

33. apteria

34. Bare area(feathers don’t grow) on the chicken skin Spaces between the feather tracts of birds Covered by down or semi-plume feathers