BIOS 255 CH 23 THE RESPIRATORY
SYSTEM
• The larynx
Answer: contains vocal folds, which produce sound when they vibrate
• The structure of voice production
Answer: The vocal folds are the principal structuresof voice production.
Vestibular folds are false vocal chords.
• Why is a male's voice deeper than a females?
Answer: Due to the influence of androgens (male sex hormones), vocal folds are usually
thicker and longer in males than in females, and therefore they vibrate more slowly. This is why
a man's voicegenerally has a lower range of pitch than that of a woman.
• Important functions / vestibular folds
Answer: When the vestibular folds (false vocalchords) are brought together, they function in
holding the breath against pressure inthe thoracic cavity, such as might occur when a person
strains to lift a heavy object.
• Trachea
Answer: extends from the larynx to the primary bronchi
• The layers of the tracheal wall:
Answer: from deep to superficial, are the (1) mucosa, (2) submucosa, (3) hyaline cartilage,
and (4) adventitia (composed of areolarconnective tissue). The mucosa of the trachea consists
of an epithelial layer of pseudostratified ciliated columnar epithelium and an underlying layer
of lamina propria that contains elastic and reticular fibers. It provides the same protection
against dust as the membrane lining the nasal cavity and larynx. The submucosa consists of
areolar connective tissue that contains seromucous glands and their ducts.
• Where does the trachea divide?
Answer: At the superior border of the fifth thoracic vertebra, it divides into a right main
(primary) bronchus (BRONG-kus = windpipe), which goes into the right lung, and a left main
(primary) bronchus, which goes intothe left lung. The right main bronchus is more vertical,
shorter, and wider than the left. As a result, an aspirated object is more likely to enter and lodge
in the right mainbronchus than the left.
• Bronchi
Answer: At the superior border of the 5th thoracic vertebrae, the trachea branches into a right
primary bronchus which enters the right lung and a left primarybronchus which enters the left
lung
, • Bronchi division
Answer: Upon entering the lungs, the primary bronchi further divideto form smaller and
smaller diameter branches
• Lungs
Answer: The lungs are enclosed and protected by the pleural membrane
• How many lobes are present in each lung?
Answer: The right lung has three lobes;the left lung has two.
• Bronchial Tree
Answer: Extensive branching from the trachea through the terminal bronchioles resembles an
inverted tree and is commonly referred to as the bronchialtree.
• Membranes protecting the lungs
Answer: Enclosed and protected by a double-layeredserous membrane called the pleural
membrane
The superficial layer = Parietal Pleura (lines the wall of the thoracic cavity)
The deep layer = Visceral Pleura (covers the lungs themselves)
Between the visceral and parietal pleurae is a small space, the pleural cavity, which
contains a small amount of lubricating fluid secreted by the membranes.This pleuralfluid
reduces friction between the membranes, allowing them to slide easily over oneanother during
breathing. Pleural fluid also causes the two membranes to adhere to one another just as a film
of water causes two glass microscope slides to stick together, a phenomenon called surface
tension.
Separate pleural cavities surround the left and right lungs.
• Lobes and Fissures of the Lungs
Answer: The oblique fissure divides the left lung intotwo lobes. The oblique and horizontal
fissures divide the right lung into three lobes.
• Why are the lungs not equal in size?
Answer: The lungs are not equal in size.The rightlung is shorter, because the liver sits high,
tucked under the ribcage, but it is broaderthan the left. The left lung is smaller because of the
space taken up by the heart
• Aveoli
Answer: Sac-like structures in the lobe of the lung. Around the circumference of the alveolar
ducts are numerous alveoli and alveolar sacs. An alveolus is a cup-shaped outpouching lined
SYSTEM
• The larynx
Answer: contains vocal folds, which produce sound when they vibrate
• The structure of voice production
Answer: The vocal folds are the principal structuresof voice production.
Vestibular folds are false vocal chords.
• Why is a male's voice deeper than a females?
Answer: Due to the influence of androgens (male sex hormones), vocal folds are usually
thicker and longer in males than in females, and therefore they vibrate more slowly. This is why
a man's voicegenerally has a lower range of pitch than that of a woman.
• Important functions / vestibular folds
Answer: When the vestibular folds (false vocalchords) are brought together, they function in
holding the breath against pressure inthe thoracic cavity, such as might occur when a person
strains to lift a heavy object.
• Trachea
Answer: extends from the larynx to the primary bronchi
• The layers of the tracheal wall:
Answer: from deep to superficial, are the (1) mucosa, (2) submucosa, (3) hyaline cartilage,
and (4) adventitia (composed of areolarconnective tissue). The mucosa of the trachea consists
of an epithelial layer of pseudostratified ciliated columnar epithelium and an underlying layer
of lamina propria that contains elastic and reticular fibers. It provides the same protection
against dust as the membrane lining the nasal cavity and larynx. The submucosa consists of
areolar connective tissue that contains seromucous glands and their ducts.
• Where does the trachea divide?
Answer: At the superior border of the fifth thoracic vertebra, it divides into a right main
(primary) bronchus (BRONG-kus = windpipe), which goes into the right lung, and a left main
(primary) bronchus, which goes intothe left lung. The right main bronchus is more vertical,
shorter, and wider than the left. As a result, an aspirated object is more likely to enter and lodge
in the right mainbronchus than the left.
• Bronchi
Answer: At the superior border of the 5th thoracic vertebrae, the trachea branches into a right
primary bronchus which enters the right lung and a left primarybronchus which enters the left
lung
, • Bronchi division
Answer: Upon entering the lungs, the primary bronchi further divideto form smaller and
smaller diameter branches
• Lungs
Answer: The lungs are enclosed and protected by the pleural membrane
• How many lobes are present in each lung?
Answer: The right lung has three lobes;the left lung has two.
• Bronchial Tree
Answer: Extensive branching from the trachea through the terminal bronchioles resembles an
inverted tree and is commonly referred to as the bronchialtree.
• Membranes protecting the lungs
Answer: Enclosed and protected by a double-layeredserous membrane called the pleural
membrane
The superficial layer = Parietal Pleura (lines the wall of the thoracic cavity)
The deep layer = Visceral Pleura (covers the lungs themselves)
Between the visceral and parietal pleurae is a small space, the pleural cavity, which
contains a small amount of lubricating fluid secreted by the membranes.This pleuralfluid
reduces friction between the membranes, allowing them to slide easily over oneanother during
breathing. Pleural fluid also causes the two membranes to adhere to one another just as a film
of water causes two glass microscope slides to stick together, a phenomenon called surface
tension.
Separate pleural cavities surround the left and right lungs.
• Lobes and Fissures of the Lungs
Answer: The oblique fissure divides the left lung intotwo lobes. The oblique and horizontal
fissures divide the right lung into three lobes.
• Why are the lungs not equal in size?
Answer: The lungs are not equal in size.The rightlung is shorter, because the liver sits high,
tucked under the ribcage, but it is broaderthan the left. The left lung is smaller because of the
space taken up by the heart
• Aveoli
Answer: Sac-like structures in the lobe of the lung. Around the circumference of the alveolar
ducts are numerous alveoli and alveolar sacs. An alveolus is a cup-shaped outpouching lined
