Deck 27: A: Physiology of the Respiratory System

Question 1

The amount of air that could be forcibly expired after normal expiration is called the functional residual capacity.

Answer 1

False

Question 2

Vital capacity is the sum of inspiratory reserve volume,tidal volume,and expiratory reserve volume.

Answer 2

True

Question 3

With emphysema,the amount of dead space air increases.

Answer 3

True

Question 4

The inspiratory capacity is equal to the sum of the tidal volume and the inspiratory reserve volume.

Question 5

Blood is distributed through the capillaries in a layer so thin that each red blood cell comes in contact with the alveolar-capillary membrane.

Question 6

Anatomical dead space contains air that does not ventilate the alveoli.

Question 7

The tendency of the lungs and thorax to return to their preinspiration volume is a physical phenomenon called elastic recoil.

Question 8

Because of tissue layers between alveolar air and the blood supply,arterial blood PO₂ is always less than alveolar PO₂.

Question 9

The partial pressure of a gas in solution is independent of the partial pressure of the same gas in the environment of the liquid.

Question 10

The major factor that determines the movement of air into or out of the lungs is a pressure gradient.

Question 11

A primary function of the respiratory system is to supply tissue with adequate oxygen and to remove carbon dioxide.

Question 12

For air to remain in the lungs,the pressure in the lungs must be equal to or less than atmospheric pressure.

Question 13

Anatomical dead space approximates 10% of the tidal volume.

Question 14

The residual volume is increased with a pneumothorax.

Question 15

Standard atmospheric pressure is usually about 760 mm Hg.

Question 16

Under usual conditions,the partial pressure of oxygen in systemic venous blood is approximately 87 mm Hg.

Question 17

The partial pressure of oxygen in an artery is always lower than the partial pressure of oxygen in a vein.

Question 18

The PO₂ is higher in the femoral artery than in the femoral vein.

Question 19

The partial pressure exerted by oxygen in a liquid is called oxygen tension.

Question 20

The anatomical dead space is approximately equal to the same number of milliliters as the individual's weight in pounds.

Question 21

Hypoventilation is characterized by low levels of carbon dioxide.

Question 22

When cells increase the rate of oxygen usage,there is an increase in the delivery of oxygen to the cells.

Question 23

The pneumotaxic center operates mainly to prevent overinflation of lung tissue.

Question 24

Dyspnea is often associated with hyperventilation.

Question 25

The best way to determine whether a conscious individual is choking is simply to ask him.

Question 26

Orthopnea can be relieved by assuming an erect posture.

Question 27

If the PCO₂ is greater in the cells than in the intercellular fluid,CO₂ will remain in the cells.

Question 28

The Hering-Breuer reflexes are activated by stretch receptors in the lungs that send messages to the inspiratory center.

Question 29

Cerebral impulses are a more powerful regulator of respirations than the carbon dioxide content of the blood.

Question 30

The Hering-Breuer reflex regulates tidal volume.

Question 31

The pneumotaxic center normally inhibits the apneustic center and the inspiratory center to permit a normal rhythm of breathing.

Question 32

In both inspiration and expiration,air moves down a pressure gradient.

Question 33

The Bohr effect describes the effect of an increased PCO₂ causing a decreased affinity between hemoglobin and oxygen.

Question 34

The Heimlich maneuver is effective because of the exertion of positive pressure on lung tissue.

Question 35

Oxygenated blood contains equal amounts of both dissolved oxygen and oxygen combined with hemoglobin.

Question 36

The diving reflex is related to the effects of hydrostatic pressure on the body.

Question 37

Both sudden painful stimulation and sudden cold stimulation to the skin can produce reflex apnea.

Question 38

Input from the apneustic center in the pons inhibits the inspiratory center causing a decrease in the length and depth of inspiration.

Question 39

An increase in the plasma PCO₂ and a decrease in PO₂ cause an increase in the dissociation of CO₂ from hemoglobin.

Question 40

Under usual conditions,the oxygen saturation of systemic venous blood is 75%.

Question 41

One reason that carbon monoxide gas is so dangerous is that it attaches to hemoglobin more readily than does oxygen gas.

Question 42

A collapsed lung has no air in it and will sink if placed in water.

Question 43

Quiet expiration is normally a passive process.

Question 44

Because residual volume cannot be voluntarily exhaled,it is not included as part of vital capacity.

Question 45

The partial pressure of oxygen in the alveolar air is equal to the partial pressure of oxygen in the systemic venous blood.

Question 46

The terms oxygen partial pressure and oxygen tension are interchangeable.

Question 47

Anatomical dead air space and physiological dead air space are interchangeable terms.

Question 48

The pressure between the visceral pleura and parietal pleura must always be positive to ensure the lung can expand.

Question 49

As lung compliance decreases,the efficiency of respiration increases.

Question 50

On a percentage basis,there is more carbon dioxide dissolved in the plasma than there is oxygen dissolved in the plasma.

Question 51

About 20% of the carbon dioxide that is carried in the blood is carried on hemoglobin attached to the acid group of an amino acid.

Question 52

Charles law deals with the relationship between pressure and volume.

Question 53

Iron is important in hemoglobin because it carries oxygen to the cells and carbon dioxide away from the cells.

Question 54

As the blood volume in the lung increases,the vital capacity increases.

Question 55

In the lung,oxygen moves down its pressure gradient,whereas carbon dioxide moves up its pressure gradient.

Question 56

For cells to get oxygen,they must have an oxygen partial pressure lower than the arterial blood serving them.

Question 57

A large amount of physiological dead air space would indicate an abnormal condition in the respiratory system.

Question 58

Contraction of the diaphragm alone can produce quiet respiration.

Question 59

One factor that determines the amount of oxygen transferred from the lungs to the blood is the total functional surface area of the respiratory membrane.

Question 60

A healthy respiratory system will still contain a certain amount of dead air space.

Question 61

There are six iron atoms in a single hemoglobin molecule.

Question 62

The enzyme in blood plasma that helps form carbaminohemoglobin is carbonic anhydrase.

Question 63

The pneumotaxic center is located in the pons of the brain.

Question 64

The apneustic center is located in the medulla of the brain.

Question 65

The formation of carbaminohemoglobin is a reversible reaction.

Question 66

The presence of hemoglobin in the blood approximately doubles the oxygen-carrying capacity of plasma alone.

Question 67

Carbonic acid forms when carbon dioxide reacts with water in the blood plasma.

Question 68

The volume of inspired air that actually reaches the alveoli is called alveolar ventilation.

Question 69

A rise in the carbon dioxide partial pressure is frequently linked to a rise in pH.

Question 70

There is one iron atom in one heme group.

Question 71

When the diaphragm contracts,it pulls the base of the ribs together,forcing air out of the lungs.

Question 72

The gas laws are based on the concept of a standard gas whose molecules are so far apart that they rarely collide.

Question 73

The chloride shift is an important step of oxygen transport in the blood.

Question 74

White blood cells do not have a role in oxygen transport.

Question 75

According to the rate laws of chemistry,the more carbon dioxide in the blood,the more carbaminohemoglobin will be formed.

Question 76

About 10% of the carbon dioxide carried in the blood is simply dissolved in the plasma.

Question 77

The expiratory center of the medulla seems to be inactive in normal,quiet breathing.

Question 78

Although interstitial fluid and intracellular fluid oxygen partial pressure are not definitely established,they are known to stay within a very narrow range.

Question 79

In the lung,as the partial pressure of oxygen of the blood goes up,the partial pressure of oxygen in the alveolar air goes down proportionally.

Question 80

Pulmonary ventilation is a technical term for what most people call breathing.