DOC PREVIEW
UNC-Chapel Hill BIOL 252 - Respiratory and Urinary

This preview shows page 1 out of 4 pages.

Save
View full document
View full document
Premium Document
Do you want full access? Go Premium and unlock all 4 pages.
Access to all documents
Download any document
Ad free experience
Premium Document
Do you want full access? Go Premium and unlock all 4 pages.
Access to all documents
Download any document
Ad free experience

Unformatted text preview:

BIOL 252 1st Edition Lecture 21 Outline of Last Lecture I. Capillary ExchangeII. Respiratory SystemIII. VentilationIV. Expiration is easyOutline of Current LectureI. How significant is pulmonary elasticity?II. VentilationIII. Resistance to AirflowIV. Respiratory VolumesV. Restrictive Pulmonary DisordersVI. Obstructive Pulmonary DisordersVII. Gas exchangeVIII. Gas transportIX. Urinary SystemX. Kidney FunctionXI. Nitrogenous WastesXII. NephronCurrent LectureI. How significant is pulmonary elasticity?a. Pneumothorax or hemothorax is compromise of pleural membranesb. Unopposed pulmonary elasticity shrinks lungs and expands pleural cavity c. Two major forces: elastic tissues surrounding alveoli & surface tensionII. Ventilationa. When you expand your thorax, expand your lungs b. Go from neutral to decrease in pressure (-3 mmHg) – Boyle’s Lawi. Inspiration => lower intrapulmonary pressurec. When expire, decrease volume, increase pressure (+3 mmHg)i. Higher intrapulmonary pressure (762 mmHg compared to atmospheric pressure of 760 mmHg)III. Resistance to Airflowa. Factors:i. Diameter of bronchi/bronchiolesThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.1. Bronchoconstriction: ACh, cold air, irritants, histamine (resting position)a. Why keep narrow under resting conditions?b. Smaller cross sectional diameter = smaller volume i. Anatomical dead space: all of the air not involved ingas exchange; if must move larger volume of air = more work; smaller volume – more (proportionally)gets to alveoli 2. Bronchodilation: catecholamines (E, NE) – sympathetic nervous systema. Increase diameter, decreases resistance, increases flowb. Advantage to getting air in more quickly – exchange of gases quicker ii. Pulmonary compliance1. Compliant lungs expand easily with expansion of thorax2. With aging, fibrosis = more rigid lungs (not as compliant)a. To pull in same volume, must work harder for each breathiii. Surface tension w/in alveoli 1. Each alveolus has tendency to collapse inward a. To reduce this effect, surfactant breaks/reduces surface tension – produced by greater alveolar cells (type II)b. If premature baby, cannot overcome collective inward force because not making enough surfactant IV. Respiratory Volumesa. Tidal Volume: 0.5 Lb. Inspiratory reserve volume: at top of tidal volume – if you inhale to capacity (howmuch more you can inspire)c. Expiratory reserve volume: how much more can we exhale? d. Vital capacity: inspiratory reserve volume, expiratory reserve volume, tidal volumee. Residual volume: amount of air that does not leave lungs after max exhalation (1.5 L)i. Keeps alveoli from collapsing ii. Why can’t we get rid of this air? Because we have a ribcage; this air is not usable V. Restrictive Pulmonary Disordersa. Restrictive disorders reduce pulmonary compliance resulting from fibrosis b. Fibrosis resulting from Tuberculosis infectionc. Result = low compliance VI. Obstructive Pulmonary Disordersa. Reduces flow (obstructs flow)b. Ex: asthma – inflammation of airwaysc. Blue curve – normal; red curve – obstructive disorder, takes longer to push air outd. FEV: forced expiratory volume, usually at 1 seci. Inhalation then blow out as hard as you can – 90% of vital capacity comesout after 1 secii. With obstructive disorder, flow reduced, cannot get out as quickly1. Affects diameter e. Which would result in condition resembling obstructive pulmonary disorder?i. Pulmonary fibrosisii. Insufficient numbers of great alveolar cellsiii. Bronchitis: decreases diameter, increases resistance, decreases flowiv. Broken ribsVII. Gas exchangea. Happens in alveoli b. Through diffusion – partial pressuresi. Force exerted on walls of container ii. Dalton’s law: each gas behaves the same way1. Ex: Oxygen is 20.9% of 760 mm Hg (159 mm Hg), which is partial pressurec. Alveolar air – what’s in your lungsi. Less N2, less O2, more H20 and more CO2ii. Know O2 is roughly 20% in air and 14% in alveolar air = 104 mmHgd. Henry’s Lawi. Amount of gas that dissolves in water is determined by its solubility in water and its partial pressure in the air ii. Partial pressure 1. As increase O2, increase amount of O2 pushed into blood iii. Solubility1. 20% O2 vs. 20% CO2 – more CO2 goes into blood because it is more soluble e. External Respirationi. We inspire air, P O2 = 104 mmHg in alveolusii. Blood coming into lungs (deoxygenated) has partial pressure of 40 mmHg iii. Less oxygen in blood coming into lungs iv. Move O2 from air into bloodv. P O2 goes from 40 mmHg to 104 mmHg – it equilibrates 1. Why not meet in the middle?VIII. Gas transporta. Oxygeni. Oxygen carried as oxyhemoglobin and dissolved in blood plasmaii. Hb + O2 HbO2IX. Urinary Systema. Excretion: secretion of wastes – eliminating something from the bodyi. Can defecate marble but do not excrete it b. Respiratory: excretes CO2, small amounts of other gases and H2Oc. Integumentary: water, inorganic salts, lactic acid, urea in sweatd. Digestive system: water, salts, CO2, bile pigments, cholesterol, metabolic wastese. Urinary: many metabolic wastes, toxin, drugs, hormones, salts, H+ and waterX. Kidney Functiona. Filter blood, removes wasteb. Regulate blood volumec. Regulate BPd. Regulate osmolarity of fluidse. Stimulate RBC productionf. Regulate acid-base balance XI. Nitrogenous Wastesa. Ammonia is formed from protein catabolism and is toxicb. Urea is formed from ammonia in the liver; less toxic than ammoniac. Uric acid is formed from nucleic acid metabolismd. Creatine is formed from breakdown of creatine phosphateXII. Nephrona. Tubule and its associated vasculatureb. The vesselsi. Glomerulus: know of capillariesii. Afferent arteriole (going in) and efferent arteriole (coming out)iii. Peritubular capillaries: vasa rectaiv. Portal system: two capillary beds1. Afferent => glomerulus => efferent => peritubular capillaryc. The tubulesi. Glomerular (Bowman’s capsule) => proximal convoluted => loop of Henle => distal convoluted => collecting


View Full Document

UNC-Chapel Hill BIOL 252 - Respiratory and Urinary

Download Respiratory and Urinary
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Respiratory and Urinary and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Respiratory and Urinary 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?