Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
Exercise Physiology
Respiratory System and Control
| Question | Answer |
|---|---|
| purpose of RS | carry O2 to and remove CO2 from all body tissues vis four processes: pulmonary ventilation and pulmonary diffusion (external resp), transport of gases via blood, capillary diffusion (international respiration) |
| what is pulmonary ventilation | process of moving air into and out of lungs in transport and exchange zones |
| path of pulmonary ventilation | nose/mouth->nasal conchae->pharynx->larynx->trachea->bronchial tree->alveoli->reverse |
| lung anatomy: pareital pleura lines thoracic wall, visceral (pulmonary) pleura attaches to lungs, lungs take size and shape of rib cage. Lung, plerual sacs, diaphragm, ribcage: determine airflow in and out of lungs | |
| inspiration vs expiration | air in vs air out |
| describe inspiration. How does it affect thoracic cavity? | active process involving muscles (diaphragm flattens, external intercostals move rib cage and sternum up and out) :. expanding thoracic cavity in 3 dimensions, expanding volume of cavity and lungs |
| apply Boyle's law to inspiration | increase in volume=decrease in pressure.. they are inverses. If lung volume increases, intrapulmonary pressure decreases, allowing air to passively rush in. |
| when would additional muscles be used in inspiration? | forced breathing uses scalenes, sternocleidomastoid, pectorals to raise ribs even farther. |
| Describe expiration in terms of passive | Passive: inspiratory muscles relax=lung volume decreases, intrapulmonary pressure increases=air forced out of lungs. |
| When is expiration not passive? | (forced breathing): internal intercostals pull ribs down, abdominal muscles force diaphragm up. also use latissimus dorsi, quadratus lumborum |
| What is the respiratory pump? | changes in intra-abdominal and intra-thoracic pressure promotes venous return to heart. ^ pressure-> venous compression, squeezing blood transmit to pulm. vein & I/S Vena cava. Decrease pressure -> venous filling. Specifically helps right atrial filling |
| review slides 11,12,13 | |
| what measures pulmonary volumes? define | spirometry: measures volumes of air inspired and expired :. measures changes in lung volume. used to measure volumes, capacities, flow rates, chronic obstructive pulmonary disease, emphysema |
| list different types of lung volumes measured by spirometry. what is this tool used for in clinical settings | total lung capacity, vital capacity, tidal volume, functional residual capacity, residual volume |
| put lung volumes on chart | |
| define tidal volume | amount of air entering and leaving lungs with each normal breath |
| define vital capacity (VC) | greatest amount of air that can be expired after maximal inspiration |
| define residual volume (RV) | amount of air remaining in lungs after maximal expiration |
| define total lung capacity (TLC) | sum of VC and residual volume (greatest amount expiration+amount of air remaining after maximal expiration) |
| What is pulmonary diffusion. what are the two major functions? | gas exchange bt aveoli and capilaries... replenishes blood oxygen supply and removes CO2 from blood |
| Path of gas exchange in pulmonary diffusion (inspiration path ad blood path) | inspired air path: bronchial tree->alveoli->blood path: RVentricle->pulm trunk-> pulm arteries-> pulm capillaries (alveoli are surround by capillaries). Reverse. |
| how much blood do lungs retrieve at rest | 4-6 L blood/min (matches flow to systemic circulation since cardiac output from right side of heart approximates cardiac output from left side of heart) |
| *?*?*?*LOW PRESSURE CIRCULATION vessels in lugs have different pressure and vascular resistance than vessels of systemic circulation. What is the mean pressure in the pulmonary artery and aorta? | |
| Pulmonary diffusion: what is the respiratory membrane? what membranes make up the respiratory membrane. What characteristics of the membrane allow optimal gas exchange? | akA alveolar-capillary membrane. Surface across which gases are exchanged. consists of alveolar wall, capillary wall, respective basement membranes. Very thin, large surface area=maximizes exchange. |
| What is dalton's law? | Total air pressure= sum of partial pressures |
| What is the atmosphere % composition? What is the total standard atmospheric pressure? | 79.04% N2, 20.93% O2, 0.03% CO2. Total 760 mm Hg :. PN2 600.7 mmHG. PO2 159.1 mmHg. PCO2 0.2 mHg) |
| What is Henry's law? How does this relate to blood? | gases dissolve in liquids in proportion to their partial pressures, depending on their solubility in specific fluids and on temperature. gas solubility in blood is constant and blood stars at constant temperature (at rest) |
| what causes a partial pressure gradient in blood? Why is this so important for diffusion? | differences in partial pressure in alveoli and blood create gradient across resp. membrane and causes gas exchange via diffusion. If pressures were equal, no exchange would occur. |
| What are the partial pressures of oxygen in the alveoli, pulmonary artery, and pulmonary vein? What is the pressure graident from alveoli to capillaries? | Alveoli: 105. P.artery: 40. P.vein: 100. Gradient: 65. |
| see slide 25 | |
| what is Fick's law? | rate of diffusion is proportional to SA and partial gas pressure, and inversely proportional to thickness of membrane gradient. area/thickness *D * (P1-P2)... (D is diffusion constant.) |
| What is PO2 gradient and PCO2 gradient in Alveoli | 65 mmHg, 6 mmHg |
| How does diffusion constant (D) influence diffusion rate? | constant differs for each gas. CO2 D higher than O2 :. CO2 diffuses easily despite lower gradient. |
| Define O2 diffusion capacity? | O2 volume diffused per min per mmHg of gradient from alveoli to blood |
| What is the mean capillary gradient for PO2? | 11 mm Hg |
| What is the resting O2 diffusion capacity in alveoli? What is the mean O2 diffusion for capillaries? | 21 mL O2/min/mmHg. 231 mL O2/min for 11mm Hg gradient |
| How does exercise affect O2 diffusion capacity? | venous O2 v = Po2 bigger gradient :. diffusion capcity 3x increase from resting rate |
| What limits resting O2 diffusion capacity in alveoli? | lungs incompletely perfuse: only 1/3 of lung is perfused and the top 2/3 lung has poor gas exchange due to gravity causing more blood to veins and arteries in bottom than at top |
| how does exercise affect lung perfusion to increase diffusion capacity? | systemic blood pressure increase opens top 2/3 perfusion :. gas exchange over full lung SA. |
| Why does diffusion of PCO2 from Partery to alveoli occur despite its small P gradient? | PCO2. diffusion constant 20x greater than O2 |
| What are the partial pressures of CO2 in the alveoli, pulmonary artery, and pulmonary vein? What is the pressure gradient from alveoli to capillaries? | Partery: 46 mmHg, alveolar: 40mmHg. Gradient=6 mmHg |
| ****Define oxygen cascade SEE SLIDE 31 | dropping of PO2 at sea level from dry ambient air to tissues and into venous circulation draining those tissues |
| see slide 32 | |
| carrying capacity of O2 per 100mL, 5L of blood | 20mL O2, 1L O2 |
| 98% O2 is bound to hemoglobin in RBCs. What is O2+Hb called? What is Hb alone called. Where does the other 2% O2 go? | oxyhemoglobin, deoxyhemoglobin, to plasma |
| What directly causes hemoglobin saturation | PO2 in blood, affinity bt O2 and Hb |
| How does PO2 influence hemoglobin saturation? | High PO2 (eg lungs) : High Po2 in blood results in almost complete Hb saturation. large drops in Po2 result in small changes in hemoglobin saturation (loading portion of curve). vice versa for low Po2 (unloading portion, Hb loses its O to tissues) |
| What factors influence hemoglobin saturation? | blood pH, blood temperature |
| How does blood pH affect the oxyhemoglobin dissociation curve? how does this factor relate to exercise? | lower pH/more acidic= curve shift right (Bohr effect: pH in lungs is high but in tissues is low, causing O to dissociated from Hb), more O2 unloaded at acidic (even lower pH) exercising muscle, |
| How does blood temperature affect the oxyhemoglobin dissociation curve? how does this factor relate to exercise? | increase temp= curve shift right. :. more O2 unloaded when blood circulates through metabolically heated active muslces. |
| The oxyhemoglobin dissociation curve represents what? A shift right means what? A shift left? | % oxyhemoglobin saturation per PO2. Shift right means more O2 (per PO2) is unloaded from Hb. Shift left means more O2 (per PO2)is loaded to Hb. |
| how much O2 ca the blood carry? How does exercise affect it? | dependent on hb content. (12-18 g/ 100mL blood) 1g Hb bind to 1.34 mL O2 (16-24 mL O2/100mL blood). At rest, about .75s to transit O2 to Hb for 98-99% saturation. exercise lowers transit time :. lower saturation. Anemic have smaller capacities. |
| how is CO2 carried through the blood? | as bicarbonate ions (60-70%), dissolved in plasma (7-10%), bound to Hb AKA carbaminohemoglobin (20-33%) |
| how does CO2 transport via the bicarbonate ion? | 60-70% transport to lungs. CO2+H2O->carbonic acid (H2CO3), occurs in RBC and catalyzed by carbonic anhydrase. H2CO3 dissociates into bicarbonate (HCO3- + H+). H= binds to Hb (buffer) & triggers Bohr effect. HCO3- diffuses from RBC to plasma |
| how does CO2 transport via plasma? | 7-10% dissolved in plasma. When PCO2 is low in lungs, CO2 comes out of plasma-CO2 solution and diffuses out of aveoli. |
| How does CO2 transport via carbaminohemoglobin? Does CO2 compete w O2 to bind to Hb? | 20-33% CO2 bound to Hb. Does not compete with O2-Hb binding bc O2 binds to heme portion and CO2 binds to globin protein portion. CO2 released to enter aveoli when PCO2 is low in lungs |
| how does PCO2 affect CO2 transport | when PCO2 is high in lungs, CO2 in plasma does not easily diffuse and the binding of CO2-Hb is easier. When PCO2 iin lungs is low, CO2 diffuses out of plasma and easily dissociates from Hb. |
| Define arterial mixed venous oxygen differnece [ (a-v)O2 ] | difference in oxygen content bt arterial blood and venous blood. Mixed venous refers to oxygen content of blood in Ratrium, which comes from all parts of body. VS not mixed, where comes from local blood (blood of exercising muscle) |
| what does (a-v)O2 reflect? describe the relationship. | reflects tissue O2 extraction. ^Extraction= v venous O2, (a-v)O2 difference ^ |
| what is the typical arterial O2 content? What about mixed/local venous O2 content? | 20 mL O2/ 100 mL blood/ at rest, 4-5 mL (mixed) and during exercise 15-16 mL O2 /100mL blood (local) |
| see slide 46 | |
| what transports O2 to muscle? How is it different from Hb and oxyHb dissociation curve? | by myoglobin, which has simialr structure to hemoglobin but a higher affinity for O2. O2-myoglobin dissociation curve shaped differently: steep slope @0-20mmHg PO2. loading@20mmHg and release at 1-2mmHg PO2 |
| See slide 48. | |
| factors influencing O2 delivery ad uptake | O2 content of blood, blood flow, local conditions (pH, temp) |
| how does O2 content of blood influence O2 delivery and uptake | represented by PO2 Hb percent saturation, creates arterial PO2 gradient for tissue exchange |
| how does blood flow of blood influence O2 delivery and uptake | v BF= v opportunity to delivery O2 to tissue.. exercise ^ blood flow to muscle. |
| how do local conditions such as pH and temperature of blood influence O2 delivery and uptake | shift O2-Hb dissociation curve. v pH or ^ temp = ^unloading in tissue |
| how is CO2 removed from muscles? | simple diffusion driven by PCO2 gradient (high PCO2 in muscle tissue, low in blood) |
| how and why does the body maintain homeostatic balance in blood? | to maintain balance of PO2, PCO2, pH. Requires coordination bt RS and CVS and occurs via involuntary regulation of pulmonary ventilation |
| what are the mechanisms of regulating pulmonary ventilation to maintain homeostatic balance in blood? | Central mechanisms: respiratory centers (expiratory, inspiratory), central chemoreceptors. Peripheral mech: peripheral chemoreceptors, mechanoreceptors |
| how do central respiratory centers (inspiratory and expiratory) regulate pulmonary ventilation? | in brain stem (medulla oblongata, pons), establish rate and depth of breathing via signals to respiratory muscles, cortex overrides signals if necessary |
| how do central chemoreceptors regulate pulmonary ventilation | stimulated by ^CO2 in cerebrospinal fluid. ^ rate and depth of breathing and remove excess CO2 from body |
| How do peripheral chemoreceptors regulate pulmonary ventilation? | in aortic bodies and carotid bodies. sensitive to blood PO2, PCO2, H+. simulates central respiratory centers to resolve |
| how do mechanoreceptors regulate pulmonary ventilation | in pleurae, bronchioles, alveoli (sense stretch). Excessive stretch -> reduced depth of breathing. Stimulates expiratory center to shorten duration of inspiration |
| what is the Hering-Breuer reflex? | chemoreceptors sense excessive stretch and relay info to expiratory center, which responds by shortening duration of inspiration to decrease risk of overinflating. Response of center is the HB reflex. |
| how does exercise affect the body's regulation of blood content? | afferent neural feedback from working limbs contributes to fast initiation of drive to breathe at beginning of exercise, proportional to frequency of limb movement. |
| how does training affect the RS in healthy individuals? | aerobic has little influence. Resting breathing frequency v, tidal volume ^, maximal pulmonary ventilation ^ to accommodate O2 demand in working muscle. Swimmers tend to have higher lung volumes, capacities, and expiratory flow rates than land based. |
| how is exercise beneficial to those aging | aging causes impaired recruitment and distension of of pulmonary capillaries during exercise. However, these do not occur in healthy older adults |
| how is exercise beneficial to those with asthma | habitual aerobic exercise is beneficial |
| how is exercise beneficial to those with pneumonia | habitual aerobic exercise is beneficial. Greater exercise E expenditure associated with lower disease risk |
Created by:
kellyyrosse
Popular Physiology sets