Respiratory System

1. Anatomy, Physiology and
Pathophysiology of Respiratory System
Presented by-
Dr. Abu Sadat Md. Sayem
M.Pharm, PhD. (University of Malaya)
Lecturer, Faculty of Pharmacy,
AIMST University

2. FACULTY : PHARMACY
PROGRAMME : BACHELOR OF PHARMACY (HONS.)
COURSE CODE : PIMC 6440204
COURSE NAME : PULMONARY, RENAL SYSTEMS & PHARMACOTHERAPY
CREDIT HOURS : 2
SEMESTER : 2
STATUS : CORE
TROPIC NAME : INTRODUCTION TO RESPIRATORY SYSTEM
Tropic Learning Outcomes
Upon successful completion of this topic, students should be able to:
 Describe the gross anatomy of lungs.
 Explain the functions of different respiratory organs.
 Describe the blood circulation in lungs.

3.  The human respiratory system is a system of organs responsible for inhaling
oxygen and exhaling carbon dioxide in humans.
 The system consists of nose, pharynx, larynx, trachea, bronchi, alveoli, lungs.
 It provides the oxygen needed by cells of the body to function according to their
designated tasks.
Human Respiratory System

4. Functions of the Respiratory System
 Filters, warms, and humidifies air
 Air Distributor
 Gas exchanger
 Influences speech
 Allows for sense of smell
Upper respiratory tract
(outside thorax)
 Nose
 Nasal Cavity
 Pharynx
 Larynx
Divisions of the Respiratory System
Lower respiratory tract (within thorax)
 Trachea
 Bronchi
 Two lungs and their coverings
 Bronchioles (the thinner air passages)
 Alveoli
 Muscles of respiration —the intercostal
muscles and the diaphragm.

5. Divisions of the Respiratory System

6.  NOSE
 The nose is the first of the
respiratory passages through which
the inspired air passes.
 It provides an entrance for air in
which air is filtered by coarse hairs
inside the nostrils.
 NASAL CAVITY
 Interior area of the nose; lined with a sticky mucous membrane and contains
tiny, surface hairs, cilia. divided medially by the nasal septum.
 The nasal conchae (also known as turbinates) are bony plates located on
the lateral wall of the nasal cavity. There are 3 nasal conches in each nasal cavity
including the superior, middle and inferior nasal conchae.
 Nasal conchae divide the cavity into passageways that are lined with mucous
membrane, and help increase the surface area available to warm and filter
incoming air.
Upper respiratory tract

7.  Pharynx (commonly known as throat)
 Location: The pharynx is a tube 12 to 14 cm long that extends from the base
of nasal cavity to the level of the 6th cervical vertebra.
 It lies behind the nose, mouth and larynx and is wider at its upper end.
 It is composed of:
Nasopharynx – uppermost portion
Oropharynx – middle portion
Laryngopharynx– lowermost portion
(or, hypopharynx)
 It serves both the respiratory and
digestive systems by receiving air from
the nasal cavity and, food and water from
oral cavity.
Upper respiratory tract

8. Upper respiratory tract
 Pharynx & Larynx

9.  Larynx
 Location: The larynx or 'voice box' extends from the root of the tongue and the
hyoid bone to the trachea. It lies in front of the laryngopharynx at the level of
the 4th, 5th and 6th cervical vertebrae.
 It is composed of a framework of muscles and cartilage bound by elastic
tissue.
 The vocal cords are two pale folds of mucous membrane which extend from
the inner wall of the thyroid prominence anteriorly to the arytenoid cartilages
posteriorly.
Upper respiratory tract
 The pitch of the sound produced
by vibrating the vocal cords in this
position is low.
 When the vocal cords are
stretched to this extent, and are
vibrated by air passing through
from the lungs, the sound
produced is high pitched.

10. Upper respiratory tract
 Role of Epiglottis

11. Functions of larynx
 Production of sound: Sound has the properties of pitch, volume and resonance.
 Pitch of the voice depends upon the length and tightness of the cords. At
puberty, the male vocal cords begin to grow longer, hence the lower pitch
of the adult male voice.
 Volume of the voice depends upon the force with which the cords vibrate.
The greater the force of expired air the more the cords vibrate and the
louder the sound emitted.
 Resonance, or tone, is dependent upon the shape of the mouth, the
position of the tongue and the lips, the facial muscles and the air in the
paranasal sinuses.
 Speech: This occurs during expiration when the sounds produced by the vocal
cords are manipulated by the tongue, cheeks and lips.
 Protection of the lower respiratory tract. During swallowing (deglutition) the
larynx moves upwards, assisting the epiglottis to close opening of trachea.
Upper respiratory tract