The skeletal system includes all of the bones and joints in the body. ... The skeletal system also provides attachment points for muscles to allow movements at the joints. New blood cells are produced by the red bone marrow inside of our bones.

1. Welcome to
presentation
Comparative account
of
axial and appendicular skeleton of amniotes
Bearing Rolls: 107424, 107449, 107466, 093460

2. Skeleton
• The word skeleton derived from Gr . word the sclero means hard
• The term skeleton refers to the hard framework of animal body
• In vertebrate it is composed of cartilage , bone or combination of
both

3. Function
• Support the animal body
• Attachment of muscle
• Protection of certain delicate vital organ

4. Classification
Dermal Skeleton Endo Skeleton
Somatic Skeleton Visceral Skeleton
Axial Skeleton Appendicular Skeleton
Skeleton

5. Axial skeleton
Which part of the endoeskeleton lies the
mid axis of the body is called the axial
skeleton Composed of -
• Skull
• Vertebral column
• Sternum
• Ribs

6. Comparative account of skull of
amniotes
Reptiles Aves Mammals
In reptilethe skull is
elongated and flattened.
Fig. skull 0f crocodile
In aves the skull is long and
dorsally convex.
Fig.skull 0f dove
In mammals the skull is
elongated and dorsally
convex except human.
Fig. skull of cat
Skull is composed of bone
except the nasal region.
Skull is composed of thin
dermal bone which full of
air for flight
adaptation,also bears
neurocranium.
Skull is composed of thin
dermal bone with
neurocranium.Some bone
is spongy.
Only one occipital condyle
present.
Only one occipital condyle
present.
Two occipital condyle
present

7. Reptiles Aves Mammals
Small crenium present Crenium is small but
elongated
Large and rounded
cranium present.
The skull roof composed
of paired frontal and
paired parietal bone
with parietal foramen.
Skull roof composed of
frontal and parietal bone
with parietal
foramen.
One frontal and one
parietal bone combined
to form skull roof
without parietal
foramen
Foramen magnum lies
posteriorly and
composed of one supra
occipital , two exo-
occipital and one basi-
occipital bone.
Foramen magnum
composed of same four
bone as reptiles but lies
the ventrally.
Four occipital bone
combined to form a
single bone , the
foramen magnum lies
the ventral side of skull.

8. Reptiles Aves Mammals
Auditory capsule
composed of
epiotic,opisthotic and pro-
otic bones.
Auditory capsule mainly
composed of pro-otic
bone.
Auditory capsule
composed of the pro-
otic,epiotic and opisthotic
bone.
Two soft nasal bone
present.
Two large “Y” shaped nasal
bone present.
Two long, narrow nasal
bone present.
Lacrimal bone small and
porous.
Lacrimal bone long and
porous.
Lacrimal bone small and
non-porous.
Homodont and pleurodont
teeth present on the pre
maxilla,maxilla and
dentaries.
Teeth absent. Teeth present on the pre
maxilla, maxilla and
dentaries.

9. Comparative account of vertebral column of
Amniotes
• In Reptiles the vertebral column is gastrocentrus type.
• Most of turtles and crocodilian vertebral column divide into-
 Cervicle
 Thoracic
 Lumber
 Sacrum
 Caudal
 In Sphenodon it is found a single short structure.
 “V” shaped chevron bones present in ventral side of the caudal vertebra.
 All kinds of centrum present in Reptiles.
• In Birds the vertebrae attached hardly one another form a strong structure.
 The cervical region is movable and modified to add wings for flying adaptation.
 The vertebrae of thoracic, lumber,sacral and caudal region are fused together and form
synsacrum.
 The synsacrum is plays a vital role for flying.
• In Mammals
 The vertebral column is gastrocentrus type.
 Except Edentata all members of mammals provide seven cervical vertebrae.

11. Comparative account of Sternum of Amniotes
Sternum of Reptiles:
• Rhomboidal and cartilazinous sternum present in
reptiles.
• Three pairs of ribs are attached with the sternum.
• Turtle, snakes and most of the leg less lizards have no
sternum.

12. Comparative account of Sternum of Amniotes
Sternum of Aves:
• Triangular sternum present in aves.
• In flying birds the mid-ventrall portion of sternum joint to
keel or carina and attach the flying muscle and gradually
it becomes “T” shaped to protect alimentary organ.
• In walking or running birds the sternum is rounded and
without keel.

13. Comparative account of Sternum of Amniotes
Sternum of Mammals:
• Lies the mid-ventrall side of pectoral girdle.
• Can be divided into three parts as-
 Pre sternum
 Menubrium
 Meso sternum
• Seven pairs of ribs attached with the sternum

14. Comparative accounts of Ribs of
Amniotes
• Ribs is long or short rod like structure
made of cartilage or bone which is
attached with the vertebral column.
• In turtle having no definite structure,
cervicle ribs absent in turtle.
• Body ribs is one side is free and
another part attached with the costal
plates of carapace.
 The ribs of birds is different in
structure.
 The ribs are arranged one above is
another.
• Ribs of birds is so strong and able to
attached the flying muscle for flying
adaptation.
• In mammals para apophysis is absent
in some times.In this case the
capitulum attached both side to the
centrum.
 Tuberculum reduced.
 Middle side of the capitulum and
tuberculum form the thoracic region.

15. Comparative account of the pectoral girdle of Amniotes
Reptiles Aves Mammals
Made of cartilage or bone. Made of bone and modified for
flight.
Made of bone modified for
running and dig hole.
Equally divide into two parts and
ventrally attached one another.
“V” shaped in structure and both
arch are not attached.
Divide by two triangular portion
and not attached one another.
“T” shaped,lies mid portion
between clavicle and ribs.
“V” shaped. ‘’V’’ shaped

16. Comparative account of pelvic girdle
Reptile Aves Mammals
Bone joint present. Bone joint absent. Bone joint present.
Wide bone joint to the sacral bone
of vertebral column.
Broad ,wide and slightly curved, divide
into pre-acetabulum and post-
acetabulum.
It is long, thick and hard bone.End
of the bone is fan like and joint to
the sacram.
Obturator foramen incomplete. Obturator foramen long and large. Obturator foramen much large.
Hypoeschium present. Absent. Absent.

17. Comparative account of Forelimb
0f amniotes
Reptiles Aves Mammals
Composed of humerous,
redious,ulna,carpal , metacarpal
and phalanges.
Composed of humerous, redious
,carpometacarpal and phalanges.
Composed of humerous,
redious,ulna,metacarpal and
phalanges.
Humerous large and weighty. Humerous broad and wide. Humerous broad, large
Carpal bone ten in number. Carpal bone two in number. Carpal bone nine in number.
Metacarpal bone five in number. Metacarpal two in number. Metacarpal five in number.

18. Comparative account of Hind limb 0f
amniotes
Reptiles Aves Mammals
Composed of fimar, tibia and
fibula,tarsal,metatarsal and
phalanges.
Composed of fimer
,tibiotersous,fibula and tarso
metatarsal and phalanges.
Composed of fimer,tibio
fibula,metatarsal and phalanges.
Patella absent. Patella present on knee joint. Patella present on knee joint.
Metatarsal six in number. Metatarsal four in number. Metatarsal three in number.

19. REFERENCE
• 1.George C. Kent, Larry Miller, Comparative
Anatomy of vertebrates, Wm. C. Brown publishers,
P-288-309.
• 2.KOTPAL.R.L, Modern text book of zoology
vertebrates, Rastogi publications, Gangotri, shinaji
road, Meerut 25002, India.
• 3.Charles k. weichert, Anatomy of chordates,
fourth edition, Mc-graw Hill International Book
Company.