Group Five presented on the respiratory systems of birds, frogs, and lizards. They discussed: - The key parts of each system including air sacs in birds, cutaneous and pulmonary respiration in frogs, and lungs in lizards. - The mechanisms of inhalation and exhalation differ between the species, with birds using air sacs and unidirectional airflow, frogs relying on buccal pumping and skin respiration, and lizards breathing solely through lungs. - Comparisons were made between the respiratory tracts and organs of each vertebrate, highlighting adaptations for their environments and modes of gas exchange.

1. Stella Maris Polytechnic University
Mother Patern College of Health Sciences
UN Drive
Monrovia, Liberia
Comparative Vertebrate Anatomy Presentation
Topic: RESPIRATION SYSTEM; BIRD/ PIGEON, FROG
AND LIZARD. GROUP Five (5)
MEMBERS: GIFTEE J. ROUMI-----ID #: 10453
BERNICE NYENPAN ---- ID#: 10557
AGNES P. BIATY ---- ID#: 10420
IMOLEAYO V. ODUWOLE ----- ID#:
10430
JESSE N. KODAH ------ID#: 10539
Pierre-yve C. Outland--------ID#10425
February. 3, 2023

2. Learning Outline
• The Respiratory system of Birds (Pigeon)
• The Respiratory system of Frog
• The Respiratory System of Lizards

3. Learning Objectives
By the end of this presentation, the students should be able to known the
follow:
• General Overview of vertebrate Respiratory system
• Associated Organs and basic pathways of the respiration
• Distinct features in some vertebrates respiratory ystem
• Basic understanding on the respiratory system of bird, frogs and
lizards
• Comparative vertebrates anatomy of the vertebrates discussed

4. Introduction of Respiratory system
The respiratory system is the organ system animals use to bring in
oxygen and get rid of carbon dioxide.
The process that brings oxygen
into our bodies called
inspiration or inhalation.
The process that sends carbon
dioxide out called expiration or
exhalation.
The human respiratory system has
many different parts that work
together to help you breathe.

6. Overview of Respiratory system of Birds/Pigeons,
Frogs and Lizards.
Respiration of Birds
AirSacs: When birds inhales,
the air first travels to the
posterior air sacs.
Next, it travels to the lungs
through a series of breathing
tubes,
Stale air travels to the anterior
air sacs, which is then
exhaled.
Respiration of Frog
Cutaneous Respiration: In
addition to inhaling and
exhaling air through their
lungs, many amphibians rely
on cutaneous respiration,
where gas exchange occurs
through the skin.
In order for cutaneous
respiration to be efficient,
the skin must remain moist.
Respiration of
Lizard
Lizard respire by
using their lungs

8. Respiration of Birds

9. Respiration of Frog

10. Respiration of Lizard

11. Birds(Pigeon)
• In birds the type of respiration is
pulmonary
• The respiratory system includes :
tract, organs and air sacs.
• A true muscular diaphragm is absent
• The repiratory tract includes: Nares,
nasal sacs, glottis, larynx, trachea and
syrinx
• The organs are the lungs and air sacs.

12. Cont.

13. Pigeon’s Respiratory tract
Larynx opens into the trachea and
is supported by a series of closely
set rings
The Trachea divides into two
bronchi- each of which divides
into smaller branches, ultimately
ending on fine air-capillaries
which lies intermingled with the
capillaries of pulmonary vessels

14. Pigeon’s respiratory organs
• Lungs are solid spongy organs;
attached dorsally to the ribs.
• There are nine air sacs
• A single pair of cervical sacs at the
base of the neck on each side
• A single median interclavicular air
sac connected to both lungs
• Two pairs of thoracic air sacs and
a pair of abdominal air sac.

15. ANATOMY OF THE NINE AIR SACS
• Posterior Thoracic: A pair of
small, posterior thoracic air sacs
is found in the posterior part of
the thoracic cavity just in front of
abdominal sacs.
• Abdominal: From the distal end of each lung arises a large
abdominal air sac. Each abdominal air sac lies along the
dorsal wall of the abdomen, ventral to the kidneys,
amongst the coils of the small intestine.
• Interclavicular:It is a median,
unpaired, somewhat triangular
air sac connected to the
secondary bronchi of both lungs.

16. ANATOMY CONT.
Cervical: A pair of small
cervical air sacs arises
anteriorly, one from each lung.
They lie at the base of the
neck, dorsal to the
interclavicular and alongside
the vertebral column.
Anterior Thoracic:From the
side of each lung arises an
anterior thoracic air sac which
lies at ventral side of lung in
the anterior portion of the
thorax, in close contact with
the ribs and the pericardium

17. Respiratory system [Frog]
• Respiration is the process of gaseous
exchange.
There are 3 types of respiration in adult
frog
I. Cutaneous respiration [skin]
II. Buccal respiration [Mouth & Throat]
III. Pulmonary respiration [Lungs]
IV. Branchial respiration [gills]

18. Respiratory system [Frog] contd.
Inhalation and exhalation of gases have 3 stages
I. External respiration [breathing]
II. Internal respiration [usage of gases]
III. Transport of gases [To and From cells]

19. Respiratory system [Frog] contd.
Cutaneous respiration occurs in aquatic habitat
• The skin of frogs is thin & richly supply with blood capillaries

20. Respiratory system [Frog] contd.
Buccal Respiration occurs on terrestrial habitat
• The mucus lining is supply with blood capillaries
• Occurs by lowering and Raising the buccal floor
• The mouth and glottis remain closed

21. Respiratory system [Frog] contd.

22. Respiratory system [Frog] contd.
Pulmonary Respiration
• In frog lungs are poorly developed
• Respiratory tract [ External nostrils, nasal chambers, internal nostril,
buccal, pharynx, glottis, larynx, bronchi
• Lungs are hydrostatic organ [Floating]

23. Respiratory system [Frog] contd.
The Larynx is a small sac whose wall by
cartilages
• 2 arytenoid and 1 cricoid cartilage
• The arytenoid are pair of semilunar
valves
• Upper edge form lateral margin of the
glottis
• Formed the Vocal cord
• Sound is produced by the expulsion of
air from lungs

24. Respiratory system [Frog] contd.
• The lungs are pair and found on the
anterior part
• They are ovoid
• Thin walls and elastic sac with internal
folds
• Division of internal folds is called septa
• The lungs is cover with peritoneum

25. Respiratory system [Frog] contd.
Pulmonary Respiration mechanism
The force pump of gaseous exchange
comes from the buccal cavity floor
These force are brought together by 2 set
of muscles
• Sternohyal muscles
O: Coracoid and clavicle or sternum
I: Hyoid apparatus in the mouth floor
• Petrohyal muscles
I: Squamous bone and hyoid apparatus

26. Respiratory system [Frog] contd.
The respiratory mechanism involves 2 phases
• Inspiration [Intake of oxygen to the lungs]
• Expiration [ Output of Carbon dioxide from lungs]

27. Respiratory system [Frog] contd.
Inspiration
• It begins with depression of the floor of the buccal cavity caused by lowering of
hyoid by sternohyoid muscle.
• Followed by opening of external nares and breathing in air. As the air reaches the
buccal cavity through internal nares, the floor of mouth is raised by upward
movement of premaxilla causing the closure of nares and simultaneous opening of
glottis.
• This forces the air into the larynx through glottis. From the larynx, the air reaches
the lungs where transfer of gases takes place.
• The inspiration takes place for quite some time before expiration begins to
maintain air in the lungs in between respirations.

28. Respiratory system [Frog] contd.
Expiration
• It begins with contraction of smooth muscles of lungs expelling air.
• It is followed by opening of glottis followed by its immediate closure.
• The air that reaches the buccal cavity is pushed out through the nares
by upward movement of the floor of the mouth.
• Most of the air that reaches the buccal cavity during expiration is
forced back to lungs in the next inspiration.
• When the frog swims in water, it keeps its snout above the water to
perform pulmonary respiration

29. Respiratory system [Frog] contd.
Tadpole has 2 gills
• External & Internal gills [
absorb and filter]

30. Respiratory system of Lizard
• Unlike frogs, Lizards have no auxiliary means of
respiration
• They breath through their lungs

31. Respiratory system of Lizard
• Respiratory structures
Trachea- divides into two
bronchii which open into the
lungs without bronchioles.
Lungs- an elastic, elongated
sac
• Have chambers called alveoli
where gaseous exchange
occurs

32. Respiratory structures of Lizard cont.
 Nares
• External and internal nares
• Leads into nasal passages or chambers.
Glottis is located behind the tongue and it opens
posteriorly into a short chamber, the larynx.
Larynx – opens into a narrow, elongated
cylindrical tube the trachea.

33. Respiration mechanism in lizards
• Pleural & peritoneal cavities communicate
• Inspiration is caused by the intercostal muscles
• Oxygen enters the bloods of the capillaries and CO2 of the blood
enters the alveoli.
• Expiration is done by lowering the ribs

34. THANK YOU!