Respiratory

Question 1

describe the functions of the respiratory system

Answer 1

main function is respiration; provides body cells with oxygen and removes waste product carbon dioxide; includes pulmonary ventilation, pulmonary gas exchange, gas transport, and tissue gas exchange

Question 2

describe how pressure and volume apply to pulmonary ventilation (negative pressure)

Answer 2

pressure-volume relationship provides driving force for pulmonary ventilation

air is a mixture of gas molecules

Boyle’s law states that at constant temperature and number of gas molecules, pressure and volume of gas are inversely related; hence as volume increases, pressure decreases and vice versa

Question 3

describe the mechanics of inspiration and expiration

Answer 3

inspiration (inhalation) brings air into the lungs

expiration (exhalation) moves air out of the lungs

Question 4

describe and distinguish between pulmonary volume and capacities

Answer 4

pulmonary volumes - measuring volumes of air that person exchanges with each breath

tidal volume - amount of air inspired or expired during normal quiet ventilation
inspiratory reserve volume - volume of air that can be forcibly inspired after normal tidal volume inspiration
expiratory reserve volume - amount of air that can be forcibly expired after normal tidal volume expiration
residual volume - air remaining in lungs after forceful expiration

pulmonary capacities:
vital capacity - total amount of exchangeable air
total lung capacity - represents total amount of exchangeable and nonexchangeable air in lungs

Question 5

describe how oxygen and carbon dioxide pressure gradients lead to net gas exchange in the lungs and tissues

Answer 5

during pulmonary gas exchange, oxygen diffuses from air in alveoli to blood in pulmonary capillaries, and carbon dioxide flows in opposite direction

as with movement of all gases, pulmonary gas exchange is driven by pressure gradients created by difference in partial pressures of oxygen and carbon dioxide between air in alveoli and blood in pulmonary capillaries

Dalton’s law - each gas in mixture exerts its own pressure; total pressure of gas mixture is the sum of partial pressures of all its component gases; partial pressure of gas in mixture determines where gas diffuses; rate of gas diffusion is determined by steepness of pressure gradient

Henry’s law - degree to which gas dissolves in liquid is proportional to both partial pressure and solubility in liquid; explains behavior of gases in air that come in contact with water in body

tissue gas exchange is the exchange of oxygen and carbon dioxide between blood and tissues; partial pressure of oxygen and carbon dioxide in systemic capillaries and tissues provide pressure gradients that drive diffusion of gases

Question 6

describe mechanisms by which oxygen and carbon dioxide are carried in the blood and released for exchange

Answer 6

carbon dioxide - blood plasma, carbaminohemoglobin, and bicarbonate ions

oxygen - hemoglobin

Question 7

explain and describe diseases of the respiratory system

Answer 7

restrictive: decrease pulmonary compliance and reduce effectiveness of inspiration by increasing alveolar surface tension and destroying elastic tissue of lungs

obstructive: increase airway resistance and decreases efficiency of expiration; traps oxygen-poor, carbon dioxide-rich air in alveoli; can lead to collapse of airways

Question 8

functions of nose and nasal cavity

Answer 8

inhaled air is warmed and humidified, debris is filtered from inhaled air, antibacterial substances are secreted, olfactory receptors are housed, and enhances resonance of voice

Question 10

describe the pharynx

Answer 10

throat; nasopharynx, oropharynx, and laryngopharynx

Question 12

describe the epiglottis

Answer 12

tip of the larynx

Question 12

describe the larynx

Answer 12

voice box; houses vocal chords; keeps food and liquids out of the remaining respiratory tract; thyroid cartilage forms shield-like anterior and superior walls of larynx; cricoid cartilage is used for emergency airway; arytenoid cartilage is involved in the sound production and are attached to the vocal chords and intrinsic muscles of larynx; corniculate cartilage are the tiny pieces capping each arytenoid and also function in sound production; cuneiform cartilage help support epiglottis in lateral walls of larynx; vestibular folds are false vocal chords that play no role in sound production; vocal ligaments are the elastic bands at the core of vocal cords and vibrate to produce sound when air passes over them

Question 13

describe the uvula

Answer 13

part of soft palate; dangly thing that triggers gag reflex

Question 14

describe glottis

Answer 14

opening through which air can travel on its way to the lungs

Question 15

distinguish between loudness and pitch

Answer 15

sound loudness is determined by force of airstream; greater force of expiration = louder sound

pitch of sound is largely determined by tension of vocal cords and speed of vibration

Question 16

describe the trachea

Answer 16

windpipe

carina is the last tracheal cartilage ring that forms “hook” that curves down and back to form partial rings that surround first branches of bronchial tree

Question 17

describe the bronchial tree

Answer 17

primary bronchi (left or right) is the beginning of bronchial tree and divide at the carina

secondary bronchi is branched from primary; 3 on right and 2 on left

bronchioles are the smallest airways

alveolar sacs are grapelike clusters of alveoli at the end of the duct and its where inspired air has arrived where gas exchange occurs

Question 18

passageway of air

Answer 18

nares – nasal cavity – nasopharynx – oropharynx – laryngopharynx – larynx – trachea – primary bronchi – secondary bronchi – tertiary bronchi – multiple branches of bronchi – bronchioles – terminal bronchioles – respiratory bronchioles – alveolar ducts – alveolar sacs

Question 19

discuss the 3 alveoli cell types

Answer 19

type 1: squamous cells that account for about 90% of cells in alveolar wall; allow for rapid diffusion of gases across cell membranes; one of the three components of respiratory membrane

type 2: small cuboidal cells that account for about 10% of cells in alveolar wall; responsible for synthesis of surfactant

alveolar macrophages: mobile phagocytes; clean up and digest debris that made its way into the alveolus

Question 20

describe the lungs

Answer 20

right lung has 3 lobes and left lung only has 2 lobes due to space for heart

hilum is the triangular depression on mediastinal surface of each lung where primary bronchi, blood and lymphatic vessels, and nerves enter and exit the lung

parietal pleura is the outer layer of serous membrane

visceral pleura is the inner layer of membrane and is continuous with the surface of the lungs

Question 21

describe pulmonary ventilation

Answer 21

between breaths: intrapulmonary pressure equals atmospheric pressure, so no air movement occurs

inspiration: inspiratory muscles contract; thoracic and lung volumes increase; intrapulmonary pressure decreases to below atmospheric pressure, so air flows into the lungs

between inspiration and expiration: intrapulmonary pressure equals atmospheric pressure, so no air movement occurs

expiration: inspiratory muscles relax; thoracic and lung volumes decrease due to elastic recoil; intrapulmonary pressure increases to above atmospheric pressure, so air flows out of the lungs

Question 22

what is the big picture of respiration

Answer 22

pulmonary ventilation: oxygen and carbon dioxide are moved between the air and the alveoli in the lungs

pulmonary gas exchange: oxygen enters and carbon dioxide exits the blood via the alveoli

gas transport: oxygen and carbon dioxide are transported by the blood

tissue gas exchange: oxygen and carbon dioxide are exchanged between the blood and the tissue cells