Lungs Flashcards
includes the oral and nasal cavities, the lungs, the series
of tubes leading to the lungs, and the chest structures responsible for moving air into and out of the lungs during breathing.
respiratory system
The respiratory system includes
Oral, nasal cavity, the lungs, the chest
the adjective referring to “lungs.”
Pulmonary
lungs consist mainly of tiny air-containing sacs called ____ which number ap- proximately 300 million in the adult.
alveoli
The ___ are the sites of gas exchange with the blood.
alveoli
The ___ are all the tubes through which air flows between the external environment and the alveoli.
airways
_____ is the movement of air from the external environment through the airways into the alveoli during breathing. _____ is movement in the opposite direction.
Inspiration (inhalation), Expiration (exhalation)
an inspiration and an expiration constitute a
respiratory cycle.
During inspiration air passes through either the nose (the most common site) or mouth into the _____, a passage common to both air and food
pharynx (throat)
The pharynx branches into two tubes: the esoph- agus, through which food passes to the stomach, and the _____, which is part of the airways.
larynx
____ houses the vocal cords
larynx
____, two folds of elastic tissue stretched horizontally across its lumen.
vocal cords
The nose, mouth, pharynx, and larynx are
termed the ____
upper airways
The larynx opens into a long tube
trachea
The first airway branches that no longer contain cartilage are termed
bronchioles
Alveoli first begin to appear in ,
respiratory bronchioles
The airways beyond the larynx can be divided into two zones:
conducting zone and respiratory zone
The _____ extends from the top of the trachea to the beginning of the respiratory bronchioles; it contains no alveoli and there is no gas exchange with the blood
conducting zone
The _____, which extends from the respiratory bronchi- oles on down, contains alveoli and is the region where gases exchange with the blood.
respiratory zone
The production of this fluid is impaired in the disease ____, the most common lethal genetic disease of Caucasians, and the mucous layer becomes thick and dehydrated, obstructing the airways. The impaired secretion is due to a defect in the chloride channels involved in the secretory process
cystic fibrosis
injured by cigarette smoke and air pollutants.
Macrophages and cilia
cells that are present in the airways and alveoli
Macrophages
Most of the air facing surface(s) of the wall are lined by a continuous layer, one cell thick, of flat epithelial cells termed
type I alveolar cells.
between these cells are thicker, specialized cells termed _____ that produce a detergent-like substance, surfactant.
type II alveolar cells
The lungs, like the heart, are situated in the____, the compartment of the body between the neck and ab- domen.
thorax
The ___ is a closed compartment that is bounded at the neck by muscles and connective tissue and completely separated from the abdomen by a large, dome-shaped sheet of skeletal muscle, the diaphragm
thorax
Each lung is surrounded by a completely closed sac, the
pleural sac,
Each lung is surrounded by a completely closed sac, the pleural sac, consisting of a thin sheet of cells calle
Pleural
two layers of pleura in each sac are so close to each other that normally they are always in vir- tual contact, but they are not attached to each other. Rather, they are separated by an extremely thin layer of
intrapleural fluid
changes in the hydrostatic pressure of the intrapleural fluid ___ cause the lungs and thoracic wall to move in and out together during normal breathing.
intrapleural pressure (Pip)
____ is defined as the exchange of air between the atmosphere and alveoli.
Ventilation
During ____ air moves into and out of the lungs because the alveolar pressure is alternately made less than and greater than atmospheric pressure
ventilation
change in lung dimensions causes a change in alveolar pressure
Boyle’s law
P1V1= P2V2
Boyle’s law
lungs are passive elastic structures — like balloons — and their volume, therefore, depends upon:
- The difference in pressure termed the transpulmonary pressure (Ptp)—between the inside and the outside of the lungs
- how stretchable the lungs are
is defined as the tendency of an elastic structure to oppose stretching or distortion.
Elastic recoil
____ is the essential factor keeping the lungs partially expanded and the chest wall partially compressed between breaths.
intrapleural pressure
___ is the most important inspiratory muscle during normal quiet breathing
diaphragm
When activation of the ____to the diaphragm causes it to contract, its dome moves downward into the abdomen, enlarging the thorax.
phrenic nerves
when surfactant is deficient is the disease known as ____ his is a leading cause of death in premature infants, in whom the surfacant- synthesizing cells may be too immature to function
respiratory distress syndrome of the newborn
type 11 alveolar cells secrete a detergent-like substance known as pulmonary ____, which markedly reduces the cohesive forces between water molecules on the alveolar surface infant can inspire only by the most strenuous ef- forts, which may ultimately cause complete exhaustion, inability to breathe, lung collapse, and death.
surfactant
___ is a disease characterized by intermittent episodes in which airway smooth muscle contracts strongly, markedly increasing airway resistance. The basic defect in____ is chronic inflammation of the airways. the causes of which vary from person to per- son and include, among others, allergy, viral infections, and sensitivity to environmental factors
Asthma
(1) emphysema,
(2) chronic bronchitis, or
(3) a combination of the two.
chronic obstructive pulmonary disease
is characterized by excessive mucus production in the bronchi and chronic inflammatory changes in the small airways. The cause of obstruction is an accumulation of mucus in the air- ways and thickening of the inflamed airways.
Chronic bronchitis
___ is used to aid a person choking on a foreign body caught in and obstructing the upper airways. A sudden increase in abdominal pressure. is produced as the rescuer’s fists, placed against the victim’s abdomen slightly above the navel ncreased abdominal pressure forces the diaphragm upward into the thorax, reducing thoracic size ncreasing alveolar pressure. The forceful expiration produced by the increased alve- olar pressure often expels the object caught in the respiratory tract
Heimlich maneuver
exists when there is an increase in the ratio of carbon dioxide production to alveolar ventilation. ___ if the alveolar ventilation cannot keep pace with the carbon dioxide production.
Hypoventilation
___ exists when there is a decrease in the ratio of carbon dioxide production to alveolar ventilation—that is, when alveolar ventilation is actually too great for the amount of carbon dioxide being produce. repre- sents increased ventilation relative to metabolism
Hyperventilation
