Respiratory Physiology

Question 1

Pulmonary Ventilation

Answer 1

Respiratory Cycle: Inspiration and Expiration

Question 2

External Respiration

Answer 2

Occurs in the lungs where oxygen diffuses into the blood and CO2 diffuses into the alveolar air.

Question 3

Internal Respiration

Answer 3

Occurs in the metabolizing tissues, where oxygen diffuses out of the blood and CO2 diffuses out of the cell.

Question 4

Air movement

Answer 4

Moves from regions of high pressure to regions of low pressure.

Question 5

During inspiration, the _______ contracts increasing the volume in the thoracic cavity.. This leads to a ______ in pressure in the lungs and air moves from the atmosphere into the lungs.

Answer 5

Ribs; Decrease

Question 6

If the diaphragm relaxes then the abdominal pressure forces the diaphragm upward, and _______ pressure in the thoracic cavity beyond that of the atmospheric pressure causing air to move ______ of the lungs.

Answer 6

High; Out

Question 7

TV

Answer 7

Tidal Volume Air exhaled after a normal inspiration (quiet breathing)

Question 8

IRV

Answer 8

Inspiratory Reserve Volume Air in excess of tidal inspiration that can be inhaled with max effort. Normal: 3.3L

Question 9

ERV

Answer 9

Expiratory Reserve Volume Air in excess of tidal expiration that can be exhaled with max effort. Normal: between 1.0 and 1.2 L

Question 10

RV

Answer 10

Residual Volume Air remaining in the lungs after max expiration, keeps alveoli inflated. Normal: 1.1 - 1.2 L

Question 11

VC

Answer 11

Vital Capacity Amount of air that can be exhaled with maximum effort after maximum inspiration. Influenced by the size of the thoracic cavity. VC = IRV + TV + ERV

Question 12

IC

Answer 12

Inspiratory Capacity Max amount of air that can be inhaled after a normal (tidal) expiration.

Question 13

FRC

Answer 13

Functional Residual Capacity Amount of air in lungs after a normal respiration (tidal)

Question 14

TLC

Answer 14

Total Lung Capacity Max amount of air lungs can hold. Sum of all 4 lung volumes. TLC = TV + IRV + ERV + RV

Question 15

Pneumothorax

Answer 15

Presence of air in pleural cavity. Allows lungs to recoil and collapse.

Question 16

Atelectasis

Answer 16

Collapse of lung (or part of lung).

Question 17

Spirometry

Answer 17

Common test used to assess how well your lungs work by measuring how much air you inhale, how much you exhale and how quickly you exhale. Used to diagnose asthma, Chronic Obstructive Pulmonary disease (COPD) and other conditions that affect breathing.

Question 18

What can affect Respiratory Volumes and Capacities

Answer 18

Age Exercise Body Size Restrictive Disorders Obstructive Disorders

Question 19

Obstructive Lung Disease

Answer 19

Not getting air out. Large over inflated lungs because air can’t get out. Asthma (airways spasm and close). Chronic bronchitis. Emphysema (lungs loose their elasticity).

Question 20

Restrictive Lung Disease

Answer 20

No problem expiring air, there is just less air. Lungs can not expand (an intake problem - like having a belt across your chest) Fibrosis (tissue gets stiff) Muscular diseases (muscular dystrophy, ALS) Obesity

Question 21

Hypercapnia

Answer 21

Too much CO2

Question 22

Respiratory Acidosis

Answer 22

If CO2 accumulates in the bloodstream, the blood becomes acidic. pH < 7.35 - Caused by failure of pulmonary ventilation. - Corrected by hyperventilation, blows off excess CO2.

Question 23

Hypocapnia

Answer 23

Too little CO2

Question 24

Respiratory Alkalosis

Answer 24

Not enough CO2 in the bloodstream, and the blood becomes alkaline. pH > 7.45 - Caused by hyperventilation. - Corrected by hypoventilation. CO2 + H20 -> H2CO3 -> HCO3- + (H+) - increases H+, lowers pH to normal.

Question 25

Forced Vital Capacity

Answer 25

AKA: Forced Expiratory Volume Maximum volume of gas expired/second during forced expiration. Exhaled from full inhalation as forcefully and rapidly as possible.

Question 26

FEV1

Answer 26

Amount of air exhaled may be measured during first second of forced breath. Healthy adult: 75-85% in 1 sec.

Question 27

Gas Exchange

Answer 27

CO2 + H2O H2CO3 HCO3- + (H+) H2CO3 (Carbonic Acid HC03- (Bicarbonate ion)

Question 28

Buffer

Answer 28

Any mechanism that resists changes in pH by converting a strong acid or base into a weak one.

Question 29

Chemical Buffer

Answer 29

A substance that binds H+ and removes it from solution as its concentration begins to rise, or releases H+ into solution as its concentration fails.

Question 30

What is the importance of the carbonic acid/bicarbonate buffer system?

Answer 30

Keeps our bodies from becoming alkalotic or acidotic.

Question 31

Hypoxia

Answer 31

Oxygen imbalances

Question 32

Hypoxemic Hypoxia

Answer 32

Usually due to inadequate pulmonary gas exchange. - High altitudes - Drowning - Aspiration - Respiratory arrest - Degenerative lung disease - CO poisoning

Question 33

Ischemic Hypoxia

Answer 33

Inadequate circulation

Question 34

Anemic Hypoxia

Answer 34

Anemia

Question 35

Histotoxic Hypoxia

Answer 35

Metabolic Poison (cyanide)

Question 36

Cyanosis

Answer 36

Blueness of skin

Question 37

Label the graph

Answer 37

1. Inspiratory reserve volume
2. Vital Capacity
3. Inspiratory Capacity
4. Tidal Volume
5. Total Lung Capacity
6. Functional Residual Capacity
7. Expiratory Reserve Volume
8. Residual Volume

Question 38

Using phenol red, what color change was observed when blowing bubbles into the water?

Answer 38

• Pink to yellow (in acidic solutions)
• pH decreased

Question 39

How successful was water in resisting pH changes when a strong acid (HCl) or a strong base (NaOH) was added?

Answer 39

Water didn’t resist change at all.

Question 40

How does the carbonic acid buffer deal with excess acid or base?

Answer 40

By shifting the equation left or right accordingly. In acidic solutions, it binds more H⁺ to make it more basic, and in basic solutions it dissacociates H⁺.