Nose: The external nose projects
from the face; its skeleton is mainly cartilaginous. Noses vary considerably in
size and shape; mainly because of differences in the nasal cartilages. The
nasal cavity is the main route of air entry. It is consist of large irregular
cavity divided into two by a septum. The roof is formed by the cribriform plate
of the ethmoid bone and sphenoid bone; frontal bones and nasal bones.
from the face; its skeleton is mainly cartilaginous. Noses vary considerably in
size and shape; mainly because of differences in the nasal cartilages. The
nasal cavity is the main route of air entry. It is consist of large irregular
cavity divided into two by a septum. The roof is formed by the cribriform plate
of the ethmoid bone and sphenoid bone; frontal bones and nasal bones.
Boundaries: The floor is formed by roof
of the mouth; which consist of hard palate in front and soft palate behind. The
medial wall is formed by the septum. The lateral wall is formed by the Maxilla,
ethmoid bone and the inferior conchae. The posterior wall is formed by the
posterior wall of their pharynx. Functionally, it is the route of passage of
air, smell and begin the process by which air is warmed, moistened and
filtered.
of the mouth; which consist of hard palate in front and soft palate behind. The
medial wall is formed by the septum. The lateral wall is formed by the Maxilla,
ethmoid bone and the inferior conchae. The posterior wall is formed by the
posterior wall of their pharynx. Functionally, it is the route of passage of
air, smell and begin the process by which air is warmed, moistened and
filtered.
Nasal cavity: The nasal cavities entered
anteriorly through the nares open posteriorly into the nasopharynx through the
conchae. The mucosa lines the nasal cavities.
anteriorly through the nares open posteriorly into the nasopharynx through the
conchae. The mucosa lines the nasal cavities.
Boundaries: The roof of the nasal
cavity is divided into three parts; frontonasal, ethmoidal and sphenoidal.
cavity is divided into three parts; frontonasal, ethmoidal and sphenoidal.
Floor: Root of the mouth, it is
formed by hard palate.
formed by hard palate.
Medially: Formed by nasal septum
Laterally: Is formed by the maxilla,
the ethmoid bone and inferior conchae.
the ethmoid bone and inferior conchae.
Function in speech and also lighten the skull. With
the presence of nasal hair in the nasal cavity help in the filtering of air.
the presence of nasal hair in the nasal cavity help in the filtering of air.
Pharynx: The Pharynx is a tube
12-14cm long which extends from the base of the skull to the level of 6th
cervical vertebrae. It is located behind the nose, mouth and larynx. It is
divided into three parts, Nasopharynx, Oropharynx and Laryngopharynx.
12-14cm long which extends from the base of the skull to the level of 6th
cervical vertebrae. It is located behind the nose, mouth and larynx. It is
divided into three parts, Nasopharynx, Oropharynx and Laryngopharynx.
Boundaries
Superiorly: The inferior surface of the
base of the skull
base of the skull
Inferiorly: It is continuous with the
oesophagus
oesophagus
Anteriorly: The wall is incomplete
because of the opening into the nose, mouth and larynx
because of the opening into the nose, mouth and larynx
Posteriorly: Alveolar tissues,
involuntary muscle and the bodies of the first six cervical vertebrate
involuntary muscle and the bodies of the first six cervical vertebrate
Function
1. Warming and humidifying of
air
air
2. Taste the olfactory nerve
ending for taste in located at the oropharynx
ending for taste in located at the oropharynx
3. Hearing the auditory tube
extends from the nasophrynx is middle ear
extends from the nasophrynx is middle ear
4. Function in speech by
acting as a resonatory chamber for sound
acting as a resonatory chamber for sound
5. It is a passage for air and
food
food
Larynx: Larynx lies at the level of
C3through C6vertebrae (C3and C6
third cervical and sixth cervical respectively) it has a phonating mechanism
designed for voice production which connect the inferior part of the pharynx
(oropharynx) with the trachea.It differ is size in adult human and also differ
in sex. It grow larger in men which explains the production of “Adam’s apple”
C3through C6vertebrae (C3and C6
third cervical and sixth cervical respectively) it has a phonating mechanism
designed for voice production which connect the inferior part of the pharynx
(oropharynx) with the trachea.It differ is size in adult human and also differ
in sex. It grow larger in men which explains the production of “Adam’s apple”
Boundaries
Superiorly: Is the hyoid bone and the
root of the tongue
root of the tongue
Inferiorly: It is continuous with the
trachea
trachea
Anteriorly: Muscles attached to the
hyoid bone and muscles of the neck
hyoid bone and muscles of the neck
Posteriorly: Largngopharynx and 3rd
to 6th cervical vertebrae
to 6th cervical vertebrae
Laterally: The lobes of the thyroid
glands
glands
Function
1. Production of sound
2. Production of speech
3. Protection of the lower
respiratory tract: It ensures that food passes into the oesophagus and not into
the lower respiratory passages
respiratory tract: It ensures that food passes into the oesophagus and not into
the lower respiratory passages
4.
Passage of air: This is between the larynx and
trachea
Passage of air: This is between the larynx and
trachea
Trachea: Trachea or wide pipe is a
fibrocartilaginous tube supported by incomplete cartilaginous trachea rings.
These rings which keep the trachea patent are deficient posteriorly where the
trachea is adjacent to the oesophagus. It extend from the larynx to the level
of T5 (5th thoracic vertebrae) where it bifurcates into
right and left primary bronchi, one bronchus going into each lungs. It is about
10-11 cm long and lies mainly in the median plane in front of the oesophagus.
It composes of three layers tissue held open by 16-20 rings.
fibrocartilaginous tube supported by incomplete cartilaginous trachea rings.
These rings which keep the trachea patent are deficient posteriorly where the
trachea is adjacent to the oesophagus. It extend from the larynx to the level
of T5 (5th thoracic vertebrae) where it bifurcates into
right and left primary bronchi, one bronchus going into each lungs. It is about
10-11 cm long and lies mainly in the median plane in front of the oesophagus.
It composes of three layers tissue held open by 16-20 rings.
Boundaries
Superiorly: Larynx
Inferiorly: Right and left bronchi
Anteriorly: Upper part of the arch of
aorta and sternum
aorta and sternum
Posteriorly: Oesophagus
Laterally: Lungs and lobes of thyroid
gland
gland
Functions
1. Support and potency: The arrangement of the
cartilage prevents twisting and obstruction of the airway as the head and neck
moves. The cartilage also prevent collapse of the trachea with pressure
difference at the end of expiration
cartilage prevents twisting and obstruction of the airway as the head and neck
moves. The cartilage also prevent collapse of the trachea with pressure
difference at the end of expiration
2. Cough reflex: Nerve endings in the
Larynx, trachea and bronchi are sensitive to irritation. The reflex cause deep
inspiration, hence closure of the glottis (vocal cord) leading to contraction
of both abdominal and respiratory muscles with released of air under pressure
expelling mucus from the mouth.
Larynx, trachea and bronchi are sensitive to irritation. The reflex cause deep
inspiration, hence closure of the glottis (vocal cord) leading to contraction
of both abdominal and respiratory muscles with released of air under pressure
expelling mucus from the mouth.
3. Warming, humidifying and filtering: For the warming,
humidifying and filtering of air.
humidifying and filtering of air.
Bronchi: The two primary bronchi are
formed when the trachea bifurcate at the sterna angle, level of T5.
formed when the trachea bifurcate at the sterna angle, level of T5.
The right bronchus: this is wider, shorter and
more vertical than the left bronchus. It is more likely to become obstructed by
an inhaled foreign body. It is about 2.5cm long. Enter the lungs at three
division into the three lobes of the right lungs.
more vertical than the left bronchus. It is more likely to become obstructed by
an inhaled foreign body. It is about 2.5cm long. Enter the lungs at three
division into the three lobes of the right lungs.
The left bronchus: This is about 5 cm long. It
is narrower than the right bronchus. On entering into the left lungs, it
divides into two lobes which fit into the two lobes of the left lungs. After
entering the hilum, the primary bronchus branches into one secondary (lobar)
bronchus for each pulmonary lobes. Thus, there are two secondary bronchi in the
left lung and three in the right.
is narrower than the right bronchus. On entering into the left lungs, it
divides into two lobes which fit into the two lobes of the left lungs. After
entering the hilum, the primary bronchus branches into one secondary (lobar)
bronchus for each pulmonary lobes. Thus, there are two secondary bronchi in the
left lung and three in the right.
Each secondary bronchus divides into tertiary
bronchi-10 in the right and 8 in the left.
bronchi-10 in the right and 8 in the left.
Functions
1.
Control the entry of air: The diameter of the
respiratory passage is altered by contraction or relaxation of the involuntary
muscle in their walls, hence regulating the volume of air entering the lungs.
These changes are controlled by the autonomic nerve supply. Parasympathetic
causing constriction while sympathetic causing dilation.
Control the entry of air: The diameter of the
respiratory passage is altered by contraction or relaxation of the involuntary
muscle in their walls, hence regulating the volume of air entering the lungs.
These changes are controlled by the autonomic nerve supply. Parasympathetic
causing constriction while sympathetic causing dilation.
2.
Warming and humidifying of air
Warming and humidifying of air
3.
Support and potency
Support and potency
4.
Removal of particulate matters
Removal of particulate matters
5.
Cough reflex
Cough reflex
Mediastinum
The central compartment that contains all other
thoracic structure; the heart, thoracic part of the great vessels, thoracic
part of the trachea, oesophagus, thymus (e.g. lymph nodes) except the lungs. The
mediastinum is divided into superior and inferior parts for the purpose of
description. The superior mediastinum extends inferiorly form the superior
thoracic aperture to the horizontal plane, which include the sternal angle
anteriorly and T4 and T5 posteriorly. The inferior
mediastrinum is between the horizontal plane and the diaphragm. It is further
divided by the pericardium into the anterior, middle and posterior parts. The
middle mediastinum contain the heart and the great vessels
thoracic structure; the heart, thoracic part of the great vessels, thoracic
part of the trachea, oesophagus, thymus (e.g. lymph nodes) except the lungs. The
mediastinum is divided into superior and inferior parts for the purpose of
description. The superior mediastinum extends inferiorly form the superior
thoracic aperture to the horizontal plane, which include the sternal angle
anteriorly and T4 and T5 posteriorly. The inferior
mediastrinum is between the horizontal plane and the diaphragm. It is further
divided by the pericardium into the anterior, middle and posterior parts. The
middle mediastinum contain the heart and the great vessels
Functions
1.
Protection of delicate organs/structure
Protection of delicate organs/structure
2.
Prevention of friction and over distention of
the heart during the cardiac cycle
Prevention of friction and over distention of
the heart during the cardiac cycle
Lungs / alveoli: The pair of lung are the
vital organs of respiration. Their main function is to oxygenate the blood by
bring inspired air into close relation with the venous blood in the pulmonary
capillaries. Living lungs are normally light, soft and spongy. They are also
elastic and recoil to approximately one-third their size when the thoracic
cavity is opened. The horizontal and oblique fissure divide the lungs into
lobes. The right lungs has three lobes, the left lungs has two. Each lungs has
an apex three surfaces (costal, mediastinal and diaphragmatic), three borders
(anterior, inferior and posterior). The functional units of the lungs are the
alveoli or air sacs. The alveolus is a pouch of about 0.2 to 0.5mm in diameter.
Each alveolus is surrounded by a basket of blood capillaries supplies by the
pulmonary artery. The barrier between the alveolar air and blood, called the
respiratory membrane, consist only of the squamous endothelia cells. In the
alveolar, the pulmonary circulation has a very low blood pressure. In the
alveolar capillaries, the mean blood pressure is 10mmHg and osmotic pressure is
25mmHg. The low capillary blood pressure also prevents the rupture of the
delicate respiratory membrane.
vital organs of respiration. Their main function is to oxygenate the blood by
bring inspired air into close relation with the venous blood in the pulmonary
capillaries. Living lungs are normally light, soft and spongy. They are also
elastic and recoil to approximately one-third their size when the thoracic
cavity is opened. The horizontal and oblique fissure divide the lungs into
lobes. The right lungs has three lobes, the left lungs has two. Each lungs has
an apex three surfaces (costal, mediastinal and diaphragmatic), three borders
(anterior, inferior and posterior). The functional units of the lungs are the
alveoli or air sacs. The alveolus is a pouch of about 0.2 to 0.5mm in diameter.
Each alveolus is surrounded by a basket of blood capillaries supplies by the
pulmonary artery. The barrier between the alveolar air and blood, called the
respiratory membrane, consist only of the squamous endothelia cells. In the
alveolar, the pulmonary circulation has a very low blood pressure. In the
alveolar capillaries, the mean blood pressure is 10mmHg and osmotic pressure is
25mmHg. The low capillary blood pressure also prevents the rupture of the
delicate respiratory membrane.
The pleurae: The surface of the lung is
covered by a serous membrane, the visceral pleura, which extends into the
fissure. The visceral pleura turns back on its self and forms the parietal
pheura, which adheres to the mediastinuim, superior surface of the diaphragm
and inner surface of the ribs cage. The space between the parietal and visceral
pleural is called pleural cavity. The two membrane are normally separated only
by a film of slippery pleural fluid. The pleurae and pleural fluid have three
functions:
covered by a serous membrane, the visceral pleura, which extends into the
fissure. The visceral pleura turns back on its self and forms the parietal
pheura, which adheres to the mediastinuim, superior surface of the diaphragm
and inner surface of the ribs cage. The space between the parietal and visceral
pleural is called pleural cavity. The two membrane are normally separated only
by a film of slippery pleural fluid. The pleurae and pleural fluid have three
functions:
1. Reduction of friction:
Fluid acts as lubricants that enables the lungs to expand and contract with
minimal friction
Fluid acts as lubricants that enables the lungs to expand and contract with
minimal friction
2. Creation of pressure
gradient: Because of low pressure, in the lungs, it help in its inflation
gradient: Because of low pressure, in the lungs, it help in its inflation
3. Compartmentalization:
Pleurae, mediastinum and pericardium compartmentalize the thoracic organs and
prevent infections of one organ from spreading easily to neighbouring organs.
Pleurae, mediastinum and pericardium compartmentalize the thoracic organs and
prevent infections of one organ from spreading easily to neighbouring organs.
