Lab Exam: Respiratory System

Question 1

What is minute ventilation (VE)?

Answer 1

total volume of air entering and leaving the respiratory system each minute

Question 2

What is the formula for minute ventilation?

Answer 2

VTxRR (breaths/min)

Question 3

What is normal VT?

Answer 3

500 mL

Question 4

What is alveolar ventilation?

Answer 4

volume of air reaching the gas exchange areas per minute

Question 5

What is the formula for alveolar ventilation?

Answer 5

(VTxRR) - (DSVxRR)

Question 6

What is hyperventilation?

Answer 6

increased breathing rate

Question 7

What does hyperventilation lead to? Why

Answer 7

• respiratory alkalosis

- carbon dioxide levels drop too low, pH in blood rises

Question 8

What are the symptoms of hyperventilation?

Answer 8

• dizziness
• extremities tingle
• headache
• weakness
• fainting

Question 9

What is hypoventilation?

Answer 9

decreased breathing rate

Question 10

What does hypoventilation lead to? Why?

Answer 10

• respiratory acidosis

- increased concentration of carbon dioxide in the blood, pH in blood drops

Question 11

What are the symptoms of hypoventilation?

Answer 11

• confusion
• tremors
• sleepiness
• headaches

Question 12

What is normal pH? Blood pH?

Answer 12

• 7.4 (ranging from 7.38-7.42)

- blood pH 7.2-7.4

Question 13

What is acidosis?

Answer 13

blood pH < 7.35

Question 14

What is alkalosis?

Answer 14

blood pH > 7.45

Question 15

What regulates pH?

Answer 15

• respiratory and renal systems

- CO2 levels

Question 16

Name 2 buffers.

Answer 16

• hemoglobin

- bicarbonate

Question 17

Describe how hemoglobin is used as a buffer.

Answer 17

• deoxyhemoglobin has greater affinity for H+

- at the tissues, hemoglobin can release O2 and bind H+ (Bohr effect)

Question 18

What is FEV1?

Answer 18

forced expiratory volume (of FVC) in 1 second

Question 19

What is normal FEV1?

Answer 19

> 80%

Question 20

What is tidal volume (TV)?

Answer 20

the volume of air breathed in and out without conscious effort

Question 21

What is inspiratory reserve volume (IRV)?

Answer 21

the additional volume of air that can be inhaled with maximum effort after a normal inspiration

Question 22

What is expiratory reserve volume (ERV)?

Answer 22

the additional volume of air that can be forcibly exhaled after normal exhalation

Question 23

What is vital capacity (VC)?

Answer 23

the total volume of air that can be exhaled after a maximal inhalation

Question 24

What is the formula for VC?

Answer 24

VC = TV + IRV + ERV

Question 25

What is residual volume (RV)?

Answer 25

the volume of air remaining in the lungs after maximum exhalation (the lungs can never be completely emptied)

Question 26

What is the formula for total lung capacity (TLC)?

Answer 26

TLC = VC + RV

Question 27

Describe obstructive disorders.

Answer 27

• increased resistance in airways
• difficult to inspire and expire
• hyperinflation, barrel chested
• FRC and TLC increase
• decreased PEFR
• ie. emphysema, chronic bronchitis, asthma

Question 28

Describe restrictive disorders.

Answer 28

• decreased lung compliance
• decreased FVC, TLC, and VC
• decreased PEFR and volume
• ie. scoliosis, pulmonary fibrosis

Question 29

What is PEFR?

Answer 29

peak expiratory flow rate

Question 30

What is normal PEFR in males?

Answer 30

~9 L/sec

Question 31

What is normal PEFR in females?

Answer 31

~7 L/sec

Question 32

What is forced vital capacity (FVC)?

Answer 32

the total exhaled air, from maximum inhalation to maximum exhalation

Question 33

____/_____ measured as a percentage.

Answer 33

FEV1/FVC

Question 34

What is peak expiratory flow (PEF)?

Answer 34

the highest point on the exhalation graph

Question 35

What are buffers?

Answer 35

• chemicals that help resist changes in pH

- help to maintain pH within a normal (very narrow) range

Question 36

CO2 is buffered in the blood by…

Answer 36

• conversion to bicarbonate

- process reverses at the lungs to get rid of CO2