{"id":407,"date":"2015-08-11T21:33:29","date_gmt":"2015-08-11T21:33:29","guid":{"rendered":"http:\/\/sites.msudenver.edu\/haysc\/?page_id=407"},"modified":"2020-03-29T21:44:59","modified_gmt":"2020-03-29T21:44:59","slug":"outline-3-bio-2320-respiratory-physiology","status":"publish","type":"page","link":"https:\/\/sites.msudenver.edu\/haysc\/biology-courses\/human-anatomy-and-physiology-ii-homepage-bio-2320\/outline-3-bio-2320-respiratory-physiology\/","title":{"rendered":"Outline-3, BIO 2320, Respiratory Physiology"},"content":{"rendered":"

C. Respiration<\/strong><\/p>\n

1. Overall function<\/p>\n

Movement of gases, gas exchange, transport of gas (oxygen and carbon dioxide)<\/em><\/p>\n

2. Pulmonary Ventilation<\/p>\n

a. Boyle’s Law<\/strong><\/p>\n

Gas pressure in closed container is inversely proportional to volume of container<\/em><\/p>\n

b. Pressure differences and air flow<\/p>\n

Air flows from area of higher pressure to lower pressure<\/em><\/p>\n

c. Atmospheric pressure<\/p>\n

760 mm Hg at sea level<\/em><\/p>\n

d. Intrapleural pressure (756mmHg)<\/p>\n

Pressure between pleural layers, helps to keep lungs expanded<\/em><\/p>\n

e. Intrapulmonary pressure<\/p>\n

Pressure inside lungs, changes with size of lungs & Boyle’s law<\/em><\/p>\n

3. Inspiration\/Inhalation<\/strong><\/p>\n

a. Diaphragm & Intercostal muscles<\/p>\n

Contract and lowers diaphragm, elevates ribs<\/em><\/p>\n

b. Volume thoracic cavity<\/p>\n

Increases<\/em><\/p>\n

c. Volume of lungs<\/p>\n

Increases<\/em><\/p>\n

d. Intrapulmonary pressure (758mmHg)<\/p>\n

As volume (container) increases, pressure drops (Boyle’s law), now air moves from atmospheric pressure (760 mm Hg) into lungs (758 mm Hg)<\/em><\/p>\n

4. Expiration\/Exhalation<\/strong><\/p>\n

a. Volume thoracic cavity<\/p>\n

Decreases<\/em><\/p>\n

b. Volume of lungs<\/p>\n

Decreases<\/em><\/p>\n

c. Intrapulmonary pressure (763mmHg)<\/p>\n

As volume decreases, pressure increases, now air moves from lungs (763 mm Hg) out to atmosphere (760 mm Hg)<\/em><\/p>\n

d. Relaxed muscles<\/p>\n

Diaphragm returns to dome shape and ribs lower<\/em><\/p>\n

e. Forced expiration<\/p>\n

Abdominal muscles and intercostal muscles can contract and further decrease size of thoracic cavity<\/em><\/p>\n

5. Factors that influence pulmonary air flow<\/p>\n

a. F=P\/R<\/p>\n

b. Diameter of airways; esp. bronchioles<\/p>\n

c. Parasympathetic & Sympathetic Stimulation<\/p>\n

6. Surface tension<\/p>\n

a. Lung collapse<\/p>\n

Surface tension tends to oppose alveoli expansion<\/em><\/p>\n

b. Pulmonary surfactant<\/strong><\/p>\n

Phospholipid\/protein made by alveolar cells that greatly reduce surface tension<\/em><\/p>\n

7. Lung volumes & capacities<\/p>\n

a. Tidal volume<\/strong><\/p>\n

Volume of air in or out of lungs at rest, 500 mls<\/em><\/p>\n

1. Respiratory rate<\/strong><\/p>\n

12 breaths\/minute at rest<\/em><\/p>\n

2. Minute respiratory volume<\/strong>[6000ml\/min]\u00a012 x 500<\/em><\/p>\n

b. Inspiratory reserve volume<\/strong>[3000,2100 mls]\n

Air that can be inspired in addition to quiet tidal volume<\/em><\/p>\n

–\u00a0Inspiratory capacity<\/strong>\u00a0[TV + IRV]\n

c. Expiratory reserve volume<\/strong>[1200,800 mls]\n

Air that can be forced out after quiet tidal volume<\/em><\/p>\n

1. Residual volume<\/strong>[1200 ml]\n

Air that cannot be expired no matter how hard you try<\/em><\/p>\n

2. Functional residual capacity<\/strong>[ERV + RV]\u00a0air left in lungs after exhaling quiet tidal volume<\/em><\/p>\n

d. Vital capacity<\/strong>[IRV + TV + ERV; 4700, 3400 mls]\u00a0Maximum amount of air that can be moved in and out of lungs<\/em><\/p>\n

e. Total lung capacity<\/strong><\/p>\n

f. Dead air volume<\/strong><\/p>\n

Air not in alveoli<\/em><\/p>\n

8. Alveolar ventilation efficiency<\/p>\n

a. R.R. x (Tid. Vol. – Dead Air Vol) = A.V. (4200)<\/p>\n

b. Double R.R. (A.V. = 8400 ml\/min)<\/p>\n

c. Double T.V. (A.V. = 10,200 ml\/min)<\/p>\n

9. Matching alveolar airflow with blood flo<\/p>\n

a. Pulmonary vessels<\/p>\n

Vessels can constrict in areas where oxygen is low<\/em><\/p>\n

b. Respiratory passageways<\/p>\n

Airways can dilate where carbon dioxide levels are high<\/em><\/p>\n

D. Gas exchange<\/p>\n

1. Partial pressure<\/p>\n

Each gas in atmosphere contributes to entire atmospheric pressure, denoted as P<\/em><\/p>\n

2. Gases in liquid<\/p>\n

Gas enters liquid and dissolves in proportion to its partial pressure<\/em><\/p>\n

3. O2<\/sub><\/em> & CO2<\/sub><\/em> exchange<\/p>\n

Inhaled air mixes with old air in lungs, PO2<\/sub><\/em>\u00a0<\/sub><\/em>is 105 mmHg in alveoli and PO2<\/sub><\/em>\u00a0<\/em>is 40 in alveolar capillaries, thus net<\/em>\u00a0<\/em>diffusion<\/em><\/strong>\u00a0<\/em><\/strong>of oxygen into blood. PCO2<\/sub><\/em>\u00a0<\/em>is 45 in alveolar capillaries and 40 in alveoli, so carbon dioxide diffuses into alveoli.<\/em><\/p>\n

E. Gas transport<\/p>\n

1. O2<\/sub><\/em> transport in blood<\/p>\n

a. Hemoglobin<\/strong><\/p>\n

Oxygen binds to heme group on hemoglobin, 4 oxygen\/hemoglobin<\/em><\/p>\n

b. PO2<\/sub><\/em><\/p>\n

PO2<\/sub><\/em>\u00a0<\/em>is the most important factor determining whether oxygen and hemoglobin combine or dissociate.<\/em><\/p>\n

c. O2<\/sub><\/em>-Hb dissociation curve<\/p>\n

If PO2<\/sub><\/em>\u00a0<\/em>is low, hemoglobin binds less oxygen, if PO2<\/sub><\/em>\u00a0<\/em>is high, hemoglobin binds more oxygen<\/em><\/p>\n

d. pH & CO2<\/sub><\/em><\/p>\n

Acidic pH, high carbon dioxide levels shift the curve to the right<\/em><\/p>\n

e. Temperature<\/p>\n

Increased temperature shifts the curve to the right<\/em><\/p>\n

DPG<\/p>\n

Increased levels of metabolic byproducts shifts the curve to the right<\/em><\/p>\n

2. CO2<\/sub> transport in blood<\/p>\n

a. 7% plasma<\/p>\n

b. 23% carbamino compounds (globin of Hemoglobin)<\/p>\n

c. 70%\u00a0bicarbonate<\/strong><\/p>\n

1. Carbonic anhydrase-enzyme<\/p>\n

CO2<\/sub><\/em><\/strong>\u00a0<\/sub><\/em><\/strong>+ H2<\/sub><\/em><\/strong>\u00a0<\/em><\/strong>O<–> H2<\/sub>CO3<\/sub><\/em><\/strong>\u00a0<\/em><\/strong><–> H+<\/sup><\/em><\/strong>\u00a0<\/sup><\/em><\/strong>+ HCO3<\/sub>–<\/sup><\/em><\/strong><\/p>\n

2. Chloride shift<\/p>\n

As bicarbonate moves out of RBC, chloride must move in etc…<\/em><\/p>\n

F. Control of respiration (ventilation)<\/p>\n

1. Medullary Rhythmicity area<\/p>\n

a. Medullary inspiratory neurons<\/strong><\/p>\n

Main control of breathing<\/em><\/p>\n

1. Pons neurons<\/p>\n

a. Pneumotaxic area (limits period of inspiration)<\/p>\n

b. Apneustic area (prolongs inspiration)<\/p>\n

2. Lung stretch receptors=Mechanoreceptors (inhibits inspiration)<\/p>\n

b. Medullary expiratory neurons<\/p>\n

Only active with exercise\/forced expiration<\/em><\/p>\n

2. Control of rate & depth of respiration<\/p>\n

a. Arterial PO2<\/sub><\/em><\/p>\n

When PO2<\/sub><\/em>\u00a0is VERY low, alveolar ventilation is stimulated<\/em><\/p>\n

b. Arterial PCO2<\/sub> [5 mmHg increase, increases ventilation by 100%]\n

The major regulator of alveolar ventilation is PCO2.<\/sub><\/em><\/strong><\/p>\n

c. Arterial pH<\/p>\n

As hydrogen ions increase, alveolar ventilation increases, but hydrogen ions can’t diffuse into CSF as well as CO2<\/sub><\/em><\/p>\n

G. Effects of exercise<\/p>\n

1. Neural signals [rate & depth increase]\n

2. PCO2<\/sub><\/em> (PO2<\/sub><\/em>& pH)<\/p>\n

3. Cardiac output<\/p>\n

4. Maximal hemoglobin saturation<\/p>\n

5. Dilate airways<\/p>\n

Respiratory Airflow Video<\/a><\/p>\n

Lung Volumes Video<\/a><\/p>\n

Partial Pressure Video<\/a><\/p>\n

Gas Exchange Video<\/a><\/p>\n

Carbon Dioxide Transport Video<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

C. Respiration 1. Overall function Movement of gases, gas exchange, transport of gas (oxygen and carbon dioxide) 2. Pulmonary Ventilation a. Boyle’s Law Gas pressure in closed container is inversely proportional to volume of container b. Pressure differences and air … Continue reading →<\/span><\/a><\/p>\n","protected":false},"author":270,"featured_media":0,"parent":209,"menu_order":0,"comment_status":"closed","ping_status":"open","template":"","meta":{"_exactmetrics_skip_tracking":false,"_exactmetrics_sitenote_active":false,"_exactmetrics_sitenote_note":"","_exactmetrics_sitenote_category":0,"footnotes":""},"class_list":["post-407","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages\/407","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/users\/270"}],"replies":[{"embeddable":true,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/comments?post=407"}],"version-history":[{"count":0,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages\/407\/revisions"}],"up":[{"embeddable":true,"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/pages\/209"}],"wp:attachment":[{"href":"https:\/\/sites.msudenver.edu\/haysc\/wp-json\/wp\/v2\/media?parent=407"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}