Respiration 2 Flashcards
A scuba diver is ascending from deep underwater. According to Boyle’s Law (P₁V₁ = P₂V₂), what will happen to the diver’s lung volume if the surrounding pressure decreases as they rise toward the surface, assuming no air is lost from the lungs?
A) Lung volume will decrease because pressure and volume are directly proportional.
B) Lung volume will remain the same because atmospheric pressure does not affect the lungs.
C) Lung volume will increase because pressure and volume are inversely proportional.
D) Lung volume will decrease initially and then stabilize due to homeostatic mechanisms.
Lung volume will increase because pressure and volume are inversely proportional.
Explanation:
Boyle’s Law states that pressure and volume have an inverse relationship (P₁V₁ = P₂V₂).
(comparing P[alv] and P[atm]) when does air come in? when does it come out?
air comes in when:
p[alv] < p[atm]
air comes out when
p[alv] > p[atm]
*know that air moves form areas of high to low pressure
P[alv] is the pressure in the alveoli that changes during ventilation; what does it determine?
the rate of airflow
The lungs have a natural tendency to collapse due to various physiological forces. Based on the principles of lung mechanics, which of the following best explains why this occurs?
A) The high surface tension in the alveoli creates an inward recoil force, promoting lung collapse.
B) The intrapleural pressure (PIP) is always greater than the alveolar pressure (PALV), pulling the lungs inward.
C) The elastic recoil of the chest wall contributes to lung collapse by actively compressing the lungs.
D) The transpulmonary pressure (PTP) is negative, leading to a net inward force on the alveoli.
mainly due to the elastic recoil
The high surface tension in the alveoli creates an inward recoil force, promoting lung collapse.
At equilibrium, when no air is moving in or out of the lungs, which of the following correctly describes the balance between the elastic recoil of the lungs and the chest wall?
A) The lungs and chest wall both recoil inward, generating a negative intrapleural pressure that keeps the lungs open.
B) The lungs tend to recoil inward while the chest wall recoils outward, creating a negative intrapleural pressure that maintains lung expansion.
C) The chest wall and lungs both recoil outward, leading to an increase in intrapleural pressure and lung expansion.
D) The inward recoil of the lungs is stronger than the outward recoil of the chest wall, causing complete lung collapse at equilibrium.
The lungs tend to recoil inward while the chest wall recoils outward, creating a negative intrapleural pressure that maintains lung expansion. (aka P[ip])
pressure occurs during flunctuating during breathing, its always sub atmospheric (negative) due to the opposing recoils of the chest in lungs
a. intraplural pressure (P[ip])
b. alveolar pressure (P[alv])
c. transpulmonary pressure (P[tp])
intraplural pressure (P[ip])
aka the pressure in your intraplueral fluid
pressure responsible for producing air flow
a. intraplural pressure (P[ip])
b. alveolar pressure (P[alv])
c. transpulmonary pressure (P[tp])
alveolar pressure (P[alv])
pressure that is responsible for keeping the alveoli opened. it is the difference between alveolar pressure and intrapleural pressure
a. intraplural pressure (P[ip])
b. alveolar pressure (P[alv])
c. transpulmonary pressure (P[tp])
transpulmonary pressure (P[tp])
When no air is flowing into or out of the lungs, which pressures are equal?
A) Alveolar pressure (Pₐₗᵥ) and intrapleural pressure (Pᵢₚ)
B) Alveolar pressure (Pₐₗᵥ) and atmospheric pressure (Pₐₜₘ)
C) Intrapleural pressure (Pᵢₚ) and atmospheric pressure (Pₐₜₘ)
D) Transpulmonary pressure (Pₜₚ) and alveolar pressure (Pₐₗᵥ)
Alveolar pressure (Pₐₗᵥ) and atmospheric pressure (Pₐₜₘ)
which two govern gas exchanges?
a. P(alv)
b. P(ip)
c. P(atm)
d. P(tp)
P(alv) - P(atm)
parameter that determines lung volume
a. intraplural pressure (P[ip])
b. alveolar pressure (P[alv])
c. transpulmonary pressure (P[tp])
transpulmonary pressure (P[tp])
what is the sequence of inspiration
- diaprham and inspiratory intercostals contract
- thorax expands
- P(ip) gets more negative
- P(tp) increases because of a lower P(ip), stronger vacuum
- lungs expand
- P(alv) gets more negative
- air flows into alveoli
what is the sequence of expiration
- diaphragm and inspiratory intercostals relax
- chest recoils inwards
- P(ip) goes to normal
- increase in P(tp)
- lungs recoil back to preinspired state
- air in alveoli is compressed
- P(alv) exceeds P(atm)
- air flows out
what are the forces that cause airway resistance?
- intertia
- friction (lungs and chest wall tissues glide past eachother
Which of the following best explains why small airways have the smallest resistance in the respiratory system?
A) Small airways must have a reduced radius to increase airflow velocity for better gas exchange.
B) The cumulative cross-sectional area of small airways is larger, but each individual airway has a smaller radius.
C) The smaller radius allows for increased airway resistance, which enhances oxygen diffusion.
D) Small airways contain more smooth muscle, which actively reduces their radius during normal breathing.
with so many small airways from terminal bronchioles; the sum of all the radiuses are abundant
b
where is airway resistance higher?
a. longer, narrow tube
b. shorter, wider tube
the longer narrow tube because any increase in radius will drastically decrease air resistance
a measure of elastic properties and how EASILY the lungs can expand.
lung compliance
what does a greater lung compliance indicate?
AT ANY GIVEN TRANSPULMONARY PRESSURE, its way easier to expand the lungs
patient has their smaller airways collapsed, floppy lungs due to elastin demage and and alveolar wall destruction, and less elastic recoil. what is their condition and what does that imply?
a. emphysema
b. normal lungs
c. pulmonary fibrosis
emphysema, they can expand their lungs abnormally
with the equation Ct=△V(L)/△P(tp), what can we know about someone with emphysema?
bc ppl with emphysema expand their lungs way more easily, that means that there are small changes in P(tp)
patient has collagen deposition in alveolar walls (asbestos, lung injury, silica dust) and their lungs are stiff
a. emphysema
b. normal lungs
c. pulmonary fibrosis
pulmonary fibrosis
for someone with pulmonary fribrosis, what happens with their P(tp) for generating changes in lung volume?
they need to have higher P(tp) changes to generate a change in volume
(remember that P(tp) is responsible for determining lung volume)
in other words, they need to breathe harder
what are two components making up lung compliance?
- elastic components of the lungs (elastin, collagen)
- surface tension
A patient with high lung compliance will likely experience which of the following physiological effects?
A) Increased difficulty in lung expansion due to stiff alveoli.
B) Reduced elastic recoil, leading to air trapping and difficulty exhaling.
C) Increased airway resistance, making inhalation more effortful.
D) Decreased functional residual capacity (FRC) due to increased lung stiffness.
High compliance means the lungs expand easily but have weak elastic recoil, making exhalation harder.
Emphysema is a classic example—lungs overinflate, leading to air trapping.
Reduced elastic recoil, leading to air trapping and difficulty exhaling.
