Respiratory System Flashcards
to supply the body tissues with oxygen and dispose of carbon dioxide generated by cellular metabolism
Respiratory System
structures where the gas exchange happens
respiratory zone
Site of Gas Exchange
alveoli are tiny, hollow sacs whose open ends are continuous with the lumens of the airways
The total surface area of _______ is very large and this permits the rapid exchange of large quantities of oxygen and carbon dioxide by diffusion
Alveoli
The structures that comprise the system are:
Nose, nasal cavity, pharynx, larynx, trachea, bronchi, lungs, alveoli
Respiration is collectively made up of 4 processes:
- Pulmonary ventilation (breathing)
- External respiration (movement of O2 from lungs into blood; CO2 from blood to lungs)
- Transport of respiratory gases in the blood
- Internal respiration (movement of O2 from blood into tissue cells; CO2 from cells into blood)
structures where no gas exchange happens
conducting zone
is also known as the “windpipe.” It has 3 layers and the mucosa has the goblet cells and cilia
trachea
kills the cilia. So coughing is the only way to keep mucus from accumulating in the lungs
Smoking
Alveoli
produce a detergent-like substance called surfactant
Type II alveolar cells
In some of the alveolar walls, ____________ permit the flow of air between alveoli
alveolar pores
Alveoli
Most of the air-facing surfaces of the wall are lined by a continuous layer, one cell thick, of flat epithelial cells termed
type I alveolar cells
covers the thoracic wall and superior face of the diaphragm
parietal pleura
form a thin double-layered serosa
pleurae
lives in the pleural cavity. This provides lubrication of the lung to prevent friction while breathing
pleural fluid
is an infection or inflammation of the pleura and often results from pneumonia. This results in a roughening of the pleura, which creates friction and a stabbing pain with each breath. As the disease progresses there is a build-up of fluid, which hinders breathing.
Pleurisy
Remember that flow is proportional to the pressure difference (Δ P) between two points and inversely proportional to the
resistance (R).
covers the external surface of the lung
visceral pleural
__________ the lung compliance, the easier it is to expand the lungs at any given change in transpulmonary pressure
greater
is defined as the exchange of air between the atmosphere and alveoli
Ventilation
flow formula
F= ΔP/R
The respiratory pressuresare always relative to
atmospheric pressure
Intrapleural Pressure fluctuates with breathing, but it is always less ___________ than Palv.
4 mm Hg
IF THE Pip EVER = to Ppul THE LUNGS WILL
IMMEDIATELY COLLAPSE!
says that at a constant temperature the pressure of a gas varies inversely with its volume.
Boyle’s law
is the pressure in the alveoli
It rises and falls with breathing, but it ALWAYS equalizes with the atmospheric pressure
Intrapulmonary Pressure
If you were to go to higher altitudes (i.e., up in the Andes Mountains), then the pressures would be different
the partial pressure of oxygen decreases with increasing altitude
pressure in the pleural cavity
Intrapleural Pressure
Transpulmonary Pressure formula
P alv– P ip
is the transmural pressure that governs the static properties of the lungs
Transpulmonary Pressure
means “across a wall” and is represented by the pressure in the inside of the structure (Pi) minus the pressure outside the structure (PO).
Transmural
considered the inverse of stiffness
Lung Compliance
Inflation of a balloon-like structure like the lungs requires an increase in the transmural pressure such that
Pi increases relative to PO
markedly reduces the cohesive forces between water molecules on the alveolar surface.
lowers the surface tension, which increases lung compliance and makes it easier to expand the lungs
Surfactant
two major determinants of lung compliance
- The stretchability of the lung tissues
- The surface tension at the air-water interfaces within the alveoli
The greatest resistance is found in the ______
sized bronchi.
medium
A lack of surfactant is a huge problem for babies
respiratory distress syndrome
is caused by destruction and collapse of the smaller airways
Emphysema
is normally very small, but changes in airway resistance follow changes in airway radii
may change in response to physical, neural, and chemical factors
Airway resistance
disease characterized by intermittent episodes in which airway smooth muscle contracts strongly, markedly increasing airway resistance
Asthma
refers to emphysema, chronic bronchitis, or a combination of the two.
These diseases cause severe difficulties not only in ventilation, but in oxygenation of the blood.
chronic obstructive pulmonary disease
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 airways and thickening of the inflamed airways.
Chronic bronchitis
Other Ventilatory Responses
- Protective reflexes: coughing, sneezing
- Voluntary control of breathing: holding your breath, laughing
- Reflexes from J receptors
is an inadequate oxygen delivery to tissues.
Hypoxia
hypoxia
poor O2 delivery because of too few RBCs or abnormal hemoglobin.
Anemic hypoxia
hypoxia
blood circulation is impaired
Ischemic hypoxia
hypoxia
the body’s cells are unable to use O2 (cyanide causes this).
Histotoxic hypoxia
hypoxia
reduced arterial O2 (can be caused by lack of oxygenated air, pulmonary problems, lack of ventilation-perfusion coupling).
Hypoxemic hypoxia
type of hypoxemic hypoxia. It is the leading cause of death from fire.
Carbon Monoxide Poisoning
is an odorless, colorless gas that competes with O2 for
the binding sites on the hemoglobin. It has a 200-times greater affinity for hemoglobin than O2 does.
CO
