What are the 5 functions of the respiratory system?
1. Provide extensive gas exchange surface area
2. move air to and from gas exchange surface area
3. protects respiratory surfaces from outside
4. produces sounds
5. participates in olfactory sense
Where is the division line for the upper and lower respiratory tracts?
the layrnx
What makes up the conduction portion of the respiratory tract?
nasal cavity to bronchioles
What makes up the respiratory portion?
bronchioles to alveoli
Why are alveoli ideal for gas exchange?
they have very thin walls and a huge surface area
The respiratory defense system consists of a series of ______________ mechanisms that removes particles and pathogens.
filtration
What are the components of the RS defenses?
Mucous cells and glands
Cilia
Filtration in nasal cavity
Alveolar macrophages
This is the inflammation of bronchial walls and causes constriction and breathing difficulty.
Bronchitis
Bronchioles branch into __________ _________.
Terminal bronchiols
True or False:
Bronchioles have no cartilage and are dominated by smooth muscle.
True
This regulates smooth muscle, controls diameter of bronchioles, and controls airflow and resistance in lungs.
Autonomic control
This is the dilation of bronchial airways, caused by sympathetic ANS activation, and reduces resistance.
Bronchodilation
This constricts the bronchi, is caused by parasympathetic ANS activation and histamine release (allergic reaction).
Bronchoconstriction
This is the result of excessive stimulation and bronchoconstriction and stimulation severely restricts airflow.
Asthma
Each terminal bronchiole delivers air to a single ________ _______.
pulmonary lobule
Each pulmonary lobule is supplied by pulmonary ________ and _______.
arteries
veins
Each terminal bronchiole branches to form several ________ ____________, where gas exchange takes place.
Respiratory bronchioles
Respiratory bronchioles are connected to alveoli along ________ _______.
alveolar ducts
Alveolar ducts end at ________ ______.
alveolar sacs
Alveolar epithelium consists of what?
simple squamous epithelium
thin, delicate pneumocytes type I
Alveolar epithelium are patrolled by what?
alveolar macrophages
Alveolar epithelium contains pneumocytes type II that produce what?
Surfactant
This is an oily secretion that contains phospholipids and proteins. It coats alveolar surfaces and reduces surface tension.
Surfactant
This is difficult respiration due to alveolar collapse and is caused when pneumocytes type II do not produce enough surfactant.
Respiratory distress syndrome
What are the three layers of the respiratory membrane?
1. Squamous epithelial cells lining the alveolus
2. Endothelial cells lining an adjacent capillary
3. Fused basement membranes between the alveolar and endothelial cells
This is the inflammation of the lobules. It causes fluid to leak into alveoli and compromises the function of respiratory membrane.
Pneumonia
The alveolar capillaries are the site of what enzyme?
ACE
Venous blood by passes the ________ circuit and flows into the pulmonary veins.
Systemic
True or false:
Blood pressure in the pulmonary circuit is low.
True
Pulmonary vessels are easily blocked by what?
Blood clots
fat
air bubbles
When a pulmonary blockage occurs, what is it called?
Pulmonary embolism
Respiration refers to what two integrated processes?
1. External respiration
2. Internal respiration
What are the three processes of external respiration?
1. Pulmonary ventilation (breathing)
2. Gas diffusion (across membranes and capillaries)
3. Transport of O2 and CO2 (between alveolar capillaries and capillary beds in other tissues)
Abnormal external respiration is dangerous. What are the two conditions that can be caused by this?
Hypoxia - low tissue oxygen levels
Anoxia - complete lack of oxygen
This is the physical movement of air in and out of the respiratory tract.
Pulmonary ventilation
The movement of air is what?
Atmospheric pressure
The aspect of air has several important physiological effects.
The weight of air
Boyles law defines?
The relationship between gas pressure and volume
What is the formula for Boyles law?
P=1/V
In a contained gas, external pressure forces molecules to do what?
move closer together
Air flows from an area of ______ pressure to an area of _______ pressure.
higher
lower
A respiratory cycle consist of?
an inspiration
an expiration
Pulmonary ventilation cause volume changes that create changes in the what?
Pressure
How does the volume of the thoracic cavity change?
with expansion or contraction of diaphragm or rib cage
This is an indicator of expandability.
Compliance
Low compliance requires _______ force.
greater
High compliance requires ______ force.
Less
What are three factors that affect compliance?
Connective tissue structure of the lungs
Level of surfactant production
Mobility of the thoracic cage
True or False:
Pressure changes during inhalation and exhalation can be measured inside or outside the lungs.
True
What is normal atmospheric pressure?
1 atm = 760 mm Hg
The intrapulmonary pressure is relative to ________ pressure.
atmospheric pressure
True or false:
In relaxed breathing, the difference between atmospheric pressure and intrapulmonary pressure is large.
False. its small
This is the maximum straining, a dangerous activity, can increase range and is known as what?
Maximum Intrapulmonary Pressure
This is the pressure in the space between parietal and visceral pleura and remains below atmospheric pressure throughout respiratory cycle.
The intrapleural pressure
These are cyclical changes in the intrapleural pressure operate the respiratory pump.
The respiratory cycle
Define tidal volume.
Amount of air moved in and out of lungs in a single respiratory cycle
When an injury to the chest wall allows air into the pleural cavity.
Pneumothorax
This is known as a collapsed lung and is the result of the pneumothorax.
Atelectasis
What are the most important muscle in the RS?
The diaphragm
External intercostal muscles of the rib
Accessory respiratory muscles
True or False:
Inhalation is always active.
True
True or False
Exhalation is always passive.
False
it can be active or passive
What role does the diaphragm play?
contraction draws air into the lungs
75% of normal air movement
What role does the external intercostal muscles play?
Assist inhalation
25% of normal air movement
What are the accessory muscles that assist in elevating the ribs?
Sternocleidomastoid
Serratus anterior
Pectoralis minor
Scalene muscles
What are the muscles used in exhalation?
Internal intercostals - depress the ribs
Abdominal muscles - compress the abdomen and force diaphragm upward
True or false:
Respiratory movements are classified by pattern of muscle activity in quiet breathing and forced breathing.
True
This involves active inhalation and passive exhalation.
Quiet breathing (eupnea)
Diaphragmatic breathing or deep breathing is dominated by what?
The diaphragm
Costal breathing or shallow breathing is dominated by what?
Rib cage movements
This is when inhalation muscles relax.
Elastic rebound
This involves active inhalation and exhalation, assisted by accessory muscles and maximum levels occur in exhaustion.
Forced breathing (hyperpnea)