Chapter 13 - Respiratory System (Exam 3)

Question 1

Cellular Respiration

Answer 1

Intracellular metabolic processes in mitochondria; Use O2, produce CO2 while deriving nrg from nutrients

Question 2

External Respiration

Answer 2

Exchange between environment and cells; air moved in and out of lungs by ventilation; gases exchanged between alveoli and blood; blood transports; exchanged between blood and tissues

Question 3

Non-respiratory Functions

Answer 3

Route for H2O loss and heat elimination; enhances venous return; maintains acid-base balance; speech; defense; removes, modifies, activates/deactivates mat’l pulm circ

Question 4

Atmospheric Pressure

Answer 4

760 mm Hg

Question 5

Intra-alveolar Pressure

Answer 5

Intra-pulmonary, 760 mm Hg

Question 6

Intra-pleural Pressure

Answer 6

Intrathoracic, within plural sac, outside lungs within thoracic cavity, 756 mm Hg

Question 7

Transmural Pressure Gradient

Answer 7

Pressure pushing out > in; net outward pressure is TPG-distending lungs; Atm P > intrapleural P-chest wall squeezed in

Question 8

Air Flow

Answer 8

Down pressure gradient; intra-alveolar P changed by altering lung volume (Boyle’s law); Resp muscle CTX-change thoracic cavity vol, therefore lung vol

Question 9

Inspiration

Answer 9

intra-alveolar P < atm P

Question 10

Expiration

Answer 10

intra-alveolar P > atm P

Question 11

Resp Muscles

Answer 11

Diaphragm (Phrenic nerve, spinal column); Intercostal (between ribs); Inspiration-active, Expiration-passive

Question 12

Airway Resistance

Answer 12

F=^P/R; radius stays same-depends on pressure gradient

Question 13

Airway Size

Answer 13

Adjusted by ANS

Question 14

PNS on Airway Size

Answer 14

Relaxed, demand for airflow low; bronchial smooth muscle ctx-bronchoconstriction

Question 15

SNS on Airway Size

Answer 15

E-bronchodilation (increased O2 demand)

[Asthma-tx w e or albuterol]

Question 16

COPD (group)

Answer 16

Inc air R due to narrowing of lower airways; need inc P for normal flow; work harder to breathe

Question 17

Chronic Bronchitis

Answer 17

Inflammatory lower resp airways-smoking, pollution, allergies; narrowed airways and mucus; coughing; bacterial infection

Question 18

Asthma

Answer 18

Thickening of airways due to inflammation and histamine-induced edema; plugging airways w thick mucus; airway hyper-responsiveness-constriction smaller airway due to spasm of smooth muscle (bronchospasm); reversible

Question 19

Emphysema

Answer 19

Collapse of smaller airways; breakdown alveolar walls; irreversible; smoking or other irritants

Question 20

COPD (single)

Answer 20

Difficulty w expiration (wheezing); air trapping; enlarged lungs (barrel-chested); more air but less gas exchange

Question 21

Elasticity of Lungs

Answer 21

Compliance, elastic recoil, elastic CT, alveolar surface tension

Question 22

Compliance

Answer 22

Effort required to stretch lungs

Question 23

Elastic Recoil

Answer 23

How readily lungs rebound

Question 24

Alveolar Surface Tension

Answer 24

Thin liquid lines alveoli; H2O molecules at surface of air-water interface more attracted to each other than air; opposes expansion of alveoli; H2O molecules pull inward; elastic recoil

Question 25

Emphysema Physiology

Answer 25

Dec elastic recoil (loss elastin and dec surface tension-loss alveolar walls); inc airway R-difficulty w expiration

Question 26

Surfactant

Answer 26

Type II cells; interspersed between H2O molecules-dec surface tension; inc lung compliance; dec recoil tendency; lung’s stability; prematurity

Question 27

Gas Exchange

Answer 27

Pulm cap and tissue cap; passive diffusion O2 and CO2; down partial pressure gradient

Question 28

Partial Pressure

Answer 28

P exerted by gas directly proportional to % of gas; every gas molecule same P no matter size; Part P-individual P of gas w/in mix

Question 29

Partial Pressure Gradient

Answer 29

Difference in Part P between cap blood and surrounding structures; exists between alveolar air and pulm caps; exists between sys cap blood and tissues

Question 30

Gas Transport

Answer 30

Oxygen in blood; 1.5% dissolved, 98.5% bound to Hb; PO2 created only by dissolved O2

Question 31

Hemoglobin

Answer 31

Oxygen bound to heme portion; 4 atoms iron; % Hb saturation-extent to which Hb bound; PO2 most impt factor in %Hb sat

Question 32

PO2 Effects on Hb

Answer 32

Inc (pulm cap)-rxn driven right-inc HbO2 (inc %Hb sat)-in lungs Hb picks up O2; Dec (tissue cap)-rxn to left, O2 released from Hb (dec %Hb sat)-O2 unloaded into tissue

Question 33

Carbon Monoxide

Answer 33

CO and O2 compete for same Hb site; Hb affinity CO 240x > O2; cannot transport O2; poisonous gas-odorless, colorless, tasteless, non-irritating-deadly

Question 34

Carbon Dioxide

Answer 34

10% dissolved, 30% bound Hb, 60% converted to bicarbonate

Question 35

Haldane Effect

Answer 35

Hb greater affinity CO2 and H+ than HbO2; unloading O2 in tissue favors picking up CO2 and H+ (Haldane); inc CO2 and H+, inc O2 release from Hb (Bohr); Haldane and Bohr effects work together O2 unloading and CO2 and H+ pick up at tissue

Question 36

Respiratory Center

Answer 36

Cyclic neural activity; adjusting level ventilation match needs for O2 uptake and CO2 removal; voluntarily adjusted to speak, sing, play a wind instrument