Respiration

Question 1

Pulmonary respiration

Answer 1

Ventilation (breathing) Exchange of oxygen and carbon dioxide in the lungs

Question 2

Cellular respiration

Answer 2

Oxygen utilization and Carbon Dioxide production by the tissues

Question 3

2 functions of the respiratory system during exercise

Answer 3

1. Gas exchange between the environment and the body
2. Regulation of acid-base balance during exercise

Question 4

Ventilation

Answer 4

Movement of air and molecules occurring in bulk flow due to pressure difference

Question 5

Inspiration

Answer 5

When atmospheric pressure is greater than intrapulmonary pressure

Question 6

Expiration

Answer 6

When intrapulmonary pressure is greater than atmospheric pressure

Question 7

Mechanics of inspiration

Answer 7

Diaphragm pushes down and ribs push out to increase volume of the lungs

Question 8

Mechanics of expiration

Answer 8

Diaphragm relaxes and ribs are pulled inward to decrease volume of lungs and increase pressure

Question 9

Where does ventilation occur at rest vs as intensity increases

Answer 9

Through the nose transitions to nose and mouth as nasal valve and nares expand

Question 10

Minute ventilation

Answer 10

(Pulmonary ventilation) amount of air moved in or out of the lungs per minute

Question 11

Tidal volume

Answer 11

Amount of air moved per breath

Question 12

Breathing frequency

Answer 12

Number of breaths per minute

Question 13

What happens to breathing frequency and tidal volume during graded exercise?

Answer 13

They both increase.

Question 14

What is ventilation controlled by at rest?

Answer 14

Somatic motor neurons in the spinal cord and the respiratory control center in the medulla oblongate

Question 15

Neural input comes from

Answer 15

Motor cortex and skeletal muscle mechanoreceptors (spindles, golgi tendon, joint pressure receptors)

Question 16

What makes up humoral chemoreceptors

Answer 16

Central chemoreceptors and peripheral chemoreceptors

Question 17

Central chemoreceptors

Answer 17

In the medulla ; controls PCO2 and H+ concentration is cerebrospinal fluid

Question 18

Peripheral chemoreceptors

Answer 18

Located in aortic and carotid bodies; responsible for PCO2, PO2, H+ and K+ in the blood

Question 19

What is ventilators control during sub maximal exercise mediated by?

Answer 19

Neural input

Question 20

V/Q ratio

Answer 20

Ventilation perfusion ration compares blood flow to ventilation. Ideally should be around 1.0

Question 21

V/Q at apex of the lungs

Answer 21

Underperfused relative to ventilation as blood pools at the base with gravity. Ventilation > blood flow 1.0<

Question 22

V/Q at the base of the lungs

Answer 22

Over perfused relative to ventilation. Ventilation < blood flow 1.0>

Question 23

Exercise induced asthma

Answer 23

Caused by contraction of smooth muscle around airway and mucus in the airway post exercise

Question 24

Exercise relationship to V/Q

Answer 24

Low to moderate intensity exercise improves V/Q

Question 25

High intensity exercise on V/Q

Answer 25

Since cardiac output increases, blood flow increases and the pulmonary capillary transit time increases leading to less saturation of red blood cell lowering the partial pressure in the arteries

Question 26

How is oxygen transported in the blood

Answer 26

99% is bound to hemoglobin called oxyhemoglobin

Question 27

What determines the amount of oxygen transported per unit volume of blood?

Answer 27

1. Hemoglobin concentration 2. Arterial oxygen saturation 3. Amount dissolved in the plasma

Question 28

Oxyhemoglobin dissociation curve direction depends on

Answer 28

1. PO2 in the blood 2. Affinity between hemoglobin and Oxygen

Question 29

PO2 at the lung

Answer 29

High PO2 therefore formation of oxyhemoglobin (loading)

Question 30

PO2 at the tissues

Answer 30

Low PO2 there fore release of O2 to the tissues (unloading)

Question 31

pH effect hemoglobin

Answer 31

Decreased pH (acidic) lowers hemoglobin O2 affinity causing rightward shift

Question 32

Rightward shift of the dissociation curve indicates

Answer 32

Offloading of oxygen to the tissues

Question 33

Temperature effect on Hemoglobin

Answer 33

Increased blood temperature lowers hemoglobin affinity promoting offloading. Rightward shift

Question 34

pH during exercise

Answer 34

Increases blood H+ levels lowering acidity and having H+ bind to hemoglobin instead of Oxygen.

Question 35

Temperature during exercise effect on hemoglobin

Answer 35

Increase in temperature during exercise weakening O2 hemoglobin affinity increasing unloading to the muscle

Question 36

2-3 DPG

Answer 36

Byproduct of RBC glycolysis. Occurs during altitude exposure and causes right shift

Question 37

Right shift on curve means

Answer 37

Greater a-VO2 difference lowering the steep portion of the curve but overall not much change at the lungs

Question 38

Myoglobin

Answer 38

Shuttles oxygen from the cell membrane to the mitochondria of skeletal and cardiac muscle fibers

Question 39

Where is myoglobin concentration highest?

Answer 39

In type 1 muscle fibers as they are the fatigue resistant fibers

Question 40

Difference between hemoglobin and myoglobin affinity for oxygen

Answer 40

Myoglobin has a higher affinity for oxygen so it binds oxygen at very low PO2 compared to hemoglobin which only binds at high PO2

Question 41

Myoglobin during transition periods from rest to exercise

Answer 41

Myoglobin O2 stores serve as a reserve.

Question 42

Myoglobin after exercise

Answer 42

Myoglobin O2 stores must be replenishes leading to higher demand for oxygen and O2 debt

Question 43

How is Carbon Dioxide transported in the blood

Answer 43

10% dissolved in plasma 20% bound to hemoglobin 70% as bicarbonate (HCO3-)

Question 44

Where is Carbon Dioxide produced at the highest concentration

Answer 44

Carbon Dioxide is produced at the highest concentrations in the tissue

Question 45

Increase in Pulmonary ventilation effect on H+

Answer 45

Increasing ventilation will get rid of Carbon Dioxide through expiration and remove H+ from the blood making pH more basic

Question 46

Decrease pulmonary ventilation effect on H+

Answer 46

Decreasing Ventilation will increase CO2 build up and increase H+ concentration (decrease pH to more acidic)

Question 47

What happens to PO2 and PCO2 at the onset of submaximal steady state

Answer 47

They are relatively unchanged

Question 48

What happens to ventilation at the onset of submaximal steady state

Answer 48

rapid increase initially and then slower rise until steady state

Question 49

PCO2 during prolonged exercise in heat

Answer 49

Little change as higher ventilation is not due to increase PCO2

Question 50

Ventilation trend during prolonged exercise in heat

Answer 50

Ventilation drifts upwards because increased blood temperature affects respiratory control center

Question 51

Ventilatory threshold (Tvent)

Answer 51

Inflection point where Ventilation increases exponentially

Question 52

Is the pulmonary system a limitation during submaximal exercise in untrained subjects

Answer 52

No since Arterial PO2 is maintained within 10-12 mmHg of resting value

Question 53

Is the pulmonary system a limitation in highly trained elected endurance athletes during maximal exercise

Answer 53

Yes since there are mechanical limitations of the lung and the respiratory muscle will fatigue after 120 min at high intensity

Question 54

Exercise induced arterial hypothermia

Answer 54

40-50% of trained subjects experience due to large desaturation of oxygen in the arteries from the blood pumping too quickly and not able to perfuse with oxygen (reduced pulmonary capillary transit time)