Physiology Block 2 Exam Questions

Question 0

What pressures are negative during inspiration relative to atmosphere?

Answer 0

pleural pressure and alveolar pressure

Question 1

Contraction of the diaphragm and intercostal muscles during inspiration results in ______ pleural pressure and _______ alveolar pressure relative to atmosphere.

Answer 1

negative, negative

Question 2

What is the sequence of events leading to airflow during inspiration?

Answer 2

Diaphragm contracts, pleural space expands creating a more negative pleural pressure which stretches the alveoli (increased transpulmonary pressure), thereby reducing alveolar pressure.

Question 3

Transpulmonary pressure _____ as lung volume increases.

Answer 3

increases

Question 4

How can lung compliance be calculated?

Answer 4

Change in lung volume divided by change in transpulmonary pressure

Question 5

What does transpulmonary pressure reflect?

Answer 5

recoil force of the lungs tending to recoil to zero volume (lung wants to be completely collapsed)

Question 6

Lung compliance is ______ in emphysema patients.

Answer 6

above normal

Question 7

Compliance is a term to quantitate ______.

Answer 7

recoil of the lungs

Question 8

Airway resistance is primarily determined by _______.

Answer 8

airway diameter

Question 9

Airway resistance is _____ in combined terminal bronchioles than in the trachea.

Answer 9

lower

Question 10

Airway resistance _____ at higher lung volumes.

Answer 10

decreases

Question 11

During maximal effort expiration from total lung capacity, flow rate ______ as lung volume decreases because _______ decreases.

Answer 11

decreases, alveolar pressure

Question 12

During maximal effort expiration from total lung capacity, pleural pressure ______ as lung volume decreases and recoil pressure _______ to ________ alveolar pressure.

Answer 12

stays the same, decreases, reduce

Question 13

During maximal effort expiration from total lung capacity, the pressure inside the airway ______ as lung volume decreases and pressure outside the airway (pleural pressure) _____.

Answer 13

decreases, stays high

Question 14

During maximal effort expiration from total lung capacity, transmural pressure is _____ outside than inside which _____ the airway.

Answer 14

higher, compresses

Question 15

In standing posture, pleural pressure is more ______ at the top of the lung than at the bottom of the lung.

Answer 15

negative

Question 16

In standing posture, transpulmonary pressure is more ______ at the top of the lung than at the bottom of the lung.

Answer 16

negative

Question 17

At any lung volume, the upper lung is _______ than the bottom.

Answer 17

more filled

Question 18

The lung is ____ compliant at the top than at the bottom.

Answer 18

less

Question 19

When inhaling from functional residual volume (FRC), the top of the lung will change volume ____ than the bottom.

Answer 19

less

Question 20

A tidal volume inspiration from residual volume is distributed primarily to the _______ of the lung.

Answer 20

top

Question 21

Why is a tidal volume inspiration from residual volume distributed primarily to the top of the lung?

Answer 21

Because airways near the bottom are compressed by the high positive pleural pressure required to exhale to residual volume.

Question 22

Pulmonary vessels vs Sytemic vessels: Which have greater compliance?

Answer 22

Pulmonary

Question 23

Pulmonary vessels vs Sytemic vessels: Which have thicker walls?

Answer 23

Systemic

Question 24

Pulmonary vessels vs Sytemic vessels: Which has higher pressure?

Answer 24

Systemic

Question 25

Pulmonary vessels vs Sytemic vessels: Which has higher blood volume?

Answer 25

Systemic

Question 26

Pulmonary vessels vs Sytemic vessels: What is the same between these vessels?

Answer 26

blood flow

Question 27

In the standing posture, the top of the lung will not be perfused when ____________.

Answer 27

alveolar pressure exceeds perfusion pressure

Question 28

Why is blood flow in some lung regions is intermittent in the standing posture?

Answer 28

Because systolic perfusion pressure rises higher than alveolar pressure but diastolic pressure falls below alveolar pressure.

Question 29

In the standing posture, blood flow in the lower lung regions is ______ because perfusion pressure is _____ than the alveolar pressure throughout the cardiac cycle.

Answer 29

continuous, greater

Question 30

In the supine position, what is the same in the lung apex and base?

Answer 30

perfusion pressure, blood flow

Question 31

In the standing posture, the distriution of blood flow is not uniform throughout each ________ plane.

Answer 31

isogravitational (under same force of gravity)

Question 32

In the standing posture, where is the ventilation/perfusion ratio highest?

Answer 32

At the top

Question 33

What happens to ventilation/perfusion ratios in the lung when the body is in supine position?

Answer 33

It becomes more uniform because the non-uniformity of the ratios throughout the lung is in part due to gravity.

Question 34

What happens to ventilation/perfusion ratio during exercise?

Answer 34

It becomes more uniform due to the increased perfusion pressure during exercise.

Question 35

At the end of expiration and inspiration ________ is zero.

Answer 35

alveolar pressure

Question 36

In a pleural pressure vs tidal volume curve, you can assume that pleural pressure equals _______.

Answer 36

transpulmonary pressure

Question 37

In a pleural pressure vs tidal volume curve, how can you calculate alveolar pressure?

Answer 37

Alveolar pressure is the horizontal distance between the middle line and the curved line

Question 38

In a pleural pressure vs tidal volume curve, given flow rate, how do you calculate airway resistance?

Answer 38

Alveolar pressure is the horizontal distance between the middle line and curved line, R = alveolar pressure/flow

Question 39

What is the generic formula for resistance, using pressure and flow?

Answer 39

Resistance = Pressure / Flow

Question 40

In a pleural pressure vs tidal volume curve, the size of the loops reflect what? What does a larger loop mean?

Answer 40

Airway resistance, the larger the loop the greater the resistance.

Question 41

Airway resistance is ______ in asthmatics because ______.

Answer 41

high, airway muscle contractions decrease airway size

Question 42

In a pleural pressure vs tidal volume curve, if the loop looks symmetrical across the middle line, then you can assume what?

Answer 42

There is no difference in expiratory and inspiratory airway resistance.

Question 43

The diffusing capacity of the lung in emphysema patients is ________ normal because of _______.

Answer 43

below, reduced surface area

Question 44

What is the diffusing capacity of the lung dependent on?

Answer 44

Mostly surface area, rate of chemical reactions in the blood, solubility of the gas, and other membrane properties.

Question 45

During exercise, the transit time of blood in the lung is ______ than at rest.

Answer 45

shorter

Question 46

During exercise, surface area is ______ because of _______.

Answer 46

increased, opening of more capillaries

Question 47

With alveolar hypoxia, the driving pressure for oxygen diffusion from alveoli to capillaries is _______; thus, equilibrium between alveoli and capillaries requires ______ time than normal.

Answer 47

reduced, more

Question 48

Pulmonary fibrosis _____ lung diffusing capacity for oxygen because of the ______________.

Answer 48

decreases, thickened alveolar-capillary membranes

Question 49

High altitude natives have above-normal _____________ due to _____________.

Answer 49

diffusing capacity for oxygen, increased surface area for diffusion

Question 50

The time requires to reach equilibrium between alveoli and capillaries is _______ for carbon dioxide than for oxygen.

Answer 50

greater

Question 51

What factors affect hemoglobin affinity for oxygen?

Answer 51

PCO2, pH, temperature, carbon monoxide, etc.