Test 3 Final

Question 1

Alveolar pressure equals

atmospheric pressure When…

Answer 1

At rest (before inspiration begins)

Question 2

Intrapleural pressure is negative When…

Answer 2

At rest (before inspiration begins)

Question 3

Lung Volume is FRC at…

Answer 3

At Rest (Before Inspiration)

Question 4

The inspiratory muscles contract and cause the volume of the thorax to increase during…

Answer 4

During Inspiration

Question 5

Intrapleural pressure becomes more negative during…

Answer 5

During Inspiration

Question 6

Lung volume increases by one TV during…

Answer 6

During inspiration

Question 7

Alveolar pressure becomes greater than atmospheric pressure during…

Answer 7

During expiration

Question 8

Intrapleural pressure returns to its resting value during

Answer 8

a normal (passive) expiration

Question 9

Sympathetic stimulation and sympathetic agonists dilate the airways via…

Answer 9

β2-receptors, increase the radius, and decrease the resistance to airflow

Question 10

Laplace’s Law), as shown in the following equation:

Answer 10

P=(2T)/R

Question 11

P in P=(2T)/R is…

Answer 11

Pressure required to keep alveolus open (dynes/cm2)

Question 12

Surfactant consists of…

Answer 12

the phospholipid DPPC, other lipids, proteins and carbohydrate. Phospholipid is the major component due to its amphipathic properties

Question 13

Compliance of the lungs describes?

Answer 13

the distensibility of the lungs and is inversely related to “stiffness”

Question 14

Mathematically, compliance is

Answer 14

the change in volume for a given change in pressure or C = V/P

Question 15

“Classically”, an asthma attack begins when an allergen is inhaled. The allergen binds to…

Answer 15

IgE antibodies on MAST CELLS in the lungs.

Question 16

The most common causes of obstructive lung disease are:

Answer 16

Chronic obstructive pulmonary disease (COPD), which includes emphysema and chronic bronchitis

Asthma

Question 17

Some conditions causing restrictive lung disease are:

Answer 17

Interstitial lung disease such as idiopathic pulmonary fibrosis

Obesity

Neuromuscular disease, such as muscular dystrophy or amyotrophic lateral sclerosis

Question 18

This measurement of respiratory volumes and capacities is important in assessing the severity of a respiratory disease and monitoring improvement or deterioration in a patient’s pulmonary function.

Answer 18

Forced Expiratory Volume 1.0 (FEV1.0)

Question 19

A healthy adult should be able to expel ______% of the vital capacity in __ second(s)

Answer 19

75-85

1.0

Question 20

Oxygen is carried in blood in two forms:

Answer 20

• dissolved in plasma (~1.5%)

* bound to hemoglobin (most important; ~98.5%)

Question 21

Hemoglobin saturation at PO2 40 mmHG

Answer 21

75% 3/4 heme groups filled

Question 22

Hemoglobin saturation at PO2 25 mmHG

Answer 22

50% 2/4 heme groups filled

Question 23

Occur when the affinity of hemoglobin for O2 is decreased.

Answer 23

Shifts to the Right

Question 24

affects of Increases in 2, 3-DPG concentration on hemoglobin dissociation curve.

Answer 24

Shifts to the Right

Question 25

_________is a decrease in arterial PO2, whereas_________ is delivery to the tissues.

Answer 25

Hypoxemia | hypoxia

Question 26

occurs when body cells are unable to use O2 even though adequate amounts are delivered. This variety of hypoxia is the consequence of metabolic poisons, such as cyanide.

Answer 26

Histotoxic hypoxia

Question 27

is indicated by reduced arterial PO2. Possible causes include disordered or abnormal ventilation-perfusion coupling, pulmonary diseases that impair ventilation, and breathing air containing scant amounts of O2.

Answer 27

Hypoxemic hypoxia

Question 28

ratio is the ratio of alveolar ventilation (V) to pulmonary blood flow

Answer 28

Ventilation-Perfusion Ratio (V/Q Ratio)

Question 29

If the frequency, tidal volume, and cardiac output are normal, the V/Q ratio is approximately...

Answer 29

0.8

Question 30

Normal V/Q ratio results in

Answer 30

an arterial PO2 of 100 mmHG, and PCO2 of 40 mmHG

Question 31

If the airways are completely blocked (e.g., by a piece of food caught in the trachea), then ventilation is zero. If blood flow is normal, then V/Q is zero, which is called a

Answer 31

Shunt

Question 32

Is primarily responsible for inspiration and generates the basic rhythm for breathing

Answer 32

Medullary Respiratory (Rhythmicity) Center Dorsal Respiratory Group (DRG)

Question 33

Inputs information from peripheral chemoreceptors and mechanoreceptors

Answer 33

Cranial Nerve 10 (CN X)

Question 34

Inputs information from peripheral chemoreceptors

Answer 34

CN IX

Question 35

Output from the DRG travels via the______ nerve to the diaphragm & external intercostals

Answer 35

phrenic

Question 36

* is primarily responsible for expiration * is not active during normal, quiet breathing, when expiration is passive * is activated (e.g., during exercise) when expiration becomes an active process

Answer 36

Medullary Respiratory Center: Ventral Respiratory Group (VRG)

Question 37

* is located in the lower pons * stimulates inspiration, producing deep and prolonged inspiratory gasps (apneusis), followed by occasional brief exhalations

Answer 37

Apneustic Center

Question 38

* is located in the upper pons * inhibits inspiration and limits the burst of action potentials in the phrenic nerve * limits the size of the TV

Answer 38

Pneumotaxic Center

Question 39

When it comes to breathing, it can temporarily override the brainstem centers

Answer 39

Cerebral Cortex

Question 40

Chemoreceptors located bilaterally in the ventrolateral medulla.

Answer 40

central chemoreceptors

Question 41

Chemoreceptors found in the aortic arch and carotid arteries.

Answer 41

peripheral chemoreceptors

Question 42

Are sensitive to the pH of the CSF

Answer 42

Central Chemoreceptors in the Medulla

Question 43

Chemoreceptors sensitive to arterial O2

Answer 43

The peripheral chemoreceptors

Question 44

In order for O2 levels to become a major stimulation for increased ventilation they must drop to at least...

Answer 44

60mmHg

Question 45

The optimal ration between bicarbonate and CO2 to have a pH of 7.4

Answer 45

20:1

Question 46

The kidneys regulate pH by:

Answer 46

Secreting H+ Reabsorbing HCO3- Synthesizing HCO3- if active this lowers PH