Ex Phys Chapter 9

Front 1

Ventilatory system

Back 1

Responsible for maintaining efficient gas exchange between internal and external environment

Front 2

Functions of ventilatory system

Back 2

Supply O2 required in metabolism, eliminate CO2 produced in metabolism, regulate hydrogen ion concentration to maintain acid base balance

Front 3

Ambient air

Back 3

Outside air

Front 4

2 parts of ventilatory system

Back 4

Conductive zone and respiratory zone

Front 5

Conductive zone

Back 5

Mouth, nose, trachea, and 2 primary bronchi.

Humidify, warm, and filter the air

Front 6

Respiratory zone

Back 6

Bronchioles and alveoli (functional part of respiration)

Front 7

Alveoli capillary membrane

Back 7

Where the gas exchange occurs

Front 8

How much O2 leaves alveoli each minute in a resting state

Back 8

250 ml or 4.1 ml a second

Trained endurance athletes can increase this uptake 20x during intense aerobic exercise

Front 9

How much CO2 diffuses into alveoli each minute

Back 9

200 ml or 3.3 ml a second

Front 10

Mechanics of inspiration

Back 10

Diaphragm contracts, flattens out, moves downward. Air in lungs expand reducing the pressure. Pressure differential sucks air in. Pressure starts to decrease until it's equal with the environment and then you expire

Front 11

Mechanics of expiration

Back 11

Air moves out from the recoil of stretched lung tissue and relaxation of inspiratory muscles. Sternum and ribs swing down while diaphragm moves toward thoracic cavity. All this decreases chest cavity volume forcing air out

Front 12

Static lung volume test

Back 12

Evaluates dimensional component for air movement within the pulmonary tract and impose no time limitation on the subject

Front 13

Dynamic lung volumes

Back 13

Evaluates power component of pulmonary performance during different phases of ventilatory excursion

Front 14

Tidal volume

Back 14

Amount of air expired in a single breath .4-1 L of air

Front 15

Inspiratory reserve volume

Back 15

Maximum inspiration, additional volume of 2.5-3.5 L above TV

Front 16

Expiratory reserve volume

Back 16

Max expiration. Additional 1-1.5 L of air can be exhaled after normal expiration

Front 17

Forced vital capacity

Back 17

Maximum inspiration and expiration. Total air moved for max both. 4-5 L in men and 3-4 L in women

Front 18

Residual lung volume

Back 18

Minimum amount of air left in lungs after maximal exhalation. 1.2-1.6 L in men. 1.0-1.2 for women

Front 19

Anatomic dead space

Back 19

Portion of inspired air that doesn't participate in gas exchange. Usually 150-250mL or 30% of resting TV.

Front 20

Physiologic dead space

Back 20

Portion if alveolar volume that doesn't participate in gas exchange due to some of the alveoli not functioning properly. Can increase due to: underperfusion of blood or COPD

Front 21

Gas concentrations

Back 21

Reflect amount of gas in a given volume.

Gas concentration = gas partial pressure x solubility

Front 22

Solubility

Back 22

Dissolving power of gas

Front 23

Gas pressures

Back 23

Force exerted by gas molecules against the surfaces they encounter

Front 24

Henry's Law

Back 24

Solubility of the gas is equal to the pressure above the liquid. If the pressure is greater above the liquid, it will have greater solubility and diffuse into the liquid

Front 25

Ambient air gas mixture

Back 25

Nitrogen (79%) Oxygen (21%) Carbon dioxide (<1%)

Front 26

Daltons Law

Back 26

Partial pressure is the pressure each gas applies to it's surrounding ****

Front 27

Barometric pressure

Back 27

Atmospheric pressure, pressure exerted by the weight of the gas contained in the atmosphere

Front 28

Partial pressure of O2

Back 28

Computed by 760 x .2093 = 159

Front 29

Tracheal air

Back 29

Air is humidified here. Total pressure of air decreased to 713. Decreases PO2 to 149

Front 30

Alveolar air

Back 30

This air is very different than ambient air. 14.5% O2 and 5.5% CO2. PO2 is equal to 100mmhg

Front 31

Gas exchanges in the body (lungs)

Back 31

Alveolar PO2 = 100

Venous PO2 = 40

Alveolar PCO2 = 40

Venous PCO2 = 46

Front 32

Gas exchange in body (tissue)

Back 32

Arterial blood PO2 = 100

Tissue PO2 = 40

Arterial blood PCO2 = 40

Tissue PCO2 = 46

Front 33

Oxygen combined with Hb

Back 33

Hb is an iron protein. Increases RBC carrying capacity of oxygen 65-70 above what is dissolved in the plasma. Each Hb molecule has 4 iron atoms that combine with 1 oxygen molecule to form oxyhemoglobin.

Front 34

Loading phase

Back 34

when O2 combines with hemoglobin, also known as saturating phase

Front 35

Oxygen carrying capacity of hemoglobin

Back 35

Each 100 mL of blood contains roughly 15-16g of Hb in men.

Each gram of Hb can combine with 1.34 mL of oxygen

Front 36

Calculating oxygen carrying capacity of Hb

Back 36

Assumes 100% saturation

Oxygen carrying capacity = Hb (g per 100 ml of blood) x oxygen caoacity of Hb

Front 37

Oxyhemoglobin dissociation curve

Back 37

Explains loading and unloading of O2 in regards to PO2. As PO2 decreases, so does % concentration of Hb and extraction rate from Hb. When PO2 drops below 60, a sharp decrease occurs in how much oxygen combines with Hb

Front 38

Bohr effect

Back 38

Increases to acidity and blood temperature causes the curve to shift downward and to the right (enhanced unloading of O2). It weakens the bonds. In intense exercise this is seen resulting in unloading of O2

Front 39

Hb saturation

Back 39

At alveolar capillary membrane the PO2 is 100. Hb is 98% saturated. 19.7 mL of O2 is bound to Hb

At tissue capillary level of PO2 is 40. Hb is 73% saturated. 15 mL of O2 is bound to Hb

Front 40

Carbon dioxide transport in blood

Back 40

1. Plasma: 7-10% it stays while the rest diffuses

2. Loose combination with Hb 20%

3. Combined with water to form bicarbonate 70%

Front 41

CO2 in plasma

Back 41

Establishes PCO2 of the blood

Front 42

CO2 and Hb

Back 42

Diffuses from tissue and combines with Hb to form a carbamino acid. It's transported to lungs and expired

Front 43

Haldane effect

Back 43

Facilitates CO2 removal from the body and explains the interaction between oxygen unloading and carbon dioxide release

Front 44

ventilatory control: neural factors

Back 44

Respiratory cycle comes ruin automatic activity of inspiratory neurons. Neural input to the respiratory control center comes from both the high brain centers and afferent pathways

Front 45

Ventilatory control during rest: humoral factors

Back 45

Chemical state of blood largely regulates pulmonary ventilation at rest.

Arterial PCO2 provides the MOST IMPORTANT respiratory stimulus at rest.

Chemoreceptors: structures that stimulate ventilation in response to increased carbon dioxide, temperature, and acidity

Front 46

Ventilatory control: chemical factors

Back 46

Arterial PO2, in exercise does not decrease to the point that stimulates ventilation by chemoreceptor activation.

Also PCO2 and H ions

Chemical stimuli can't fully explain hyoerpnea (fast breathing) during physical activity

Front 47

Pulmonary ventilation

Back 47

Process of breathing (minute ventilation)

Physical activity provides greatest stimulus for increases in pulmonary ventilation

Front 48

Ventilatory equivalent for oxygen

Back 48

Ratio of minute ventilation to oxygen uptake. Represents breathing economy. Reflects amount of air breathed (VE) per oxygen consumed (VO2)

VE/VO2

Front 49

Ventilatory equivalent for carbon dioxide

Back 49

Ratio of minute ventilation to carbon dioxide produced

VE/VCO2

Front 50

Ventilation during non steady state exercise

Back 50

As VO2 increases there is a point where minute ventilation increases disproportionately. This is at the ventilatory threshold

Front 51

Ventilatory threshold

Back 51

Point at which Pulmonary ventilation increases disproportionately. Relates to carbon dioxides increases output from the buffering of lactate that begins to accumulate from anaerobic metabolism

Front 52

Onset of blood lactate accumulation

Back 52

Indicated by sharp upswing in pulmonary ventilation related to VO2 during exercise. Imbalance between BL appearance and disappearance. Occurs between 55-60% of VO2max in healthy untrained individuals and 80% of VO2max in highly trained endurance athletes

Front 53

Buffering

Back 53

Chemical buffers consist of a weak acid and a salt of that acid. Bicarbonate is main one. Anaerobic exercise increases demand for buffering