Respiratory System

• distribute air
• exchange gas (supply cells with O2, remove CO2)

oxygen obtained from environment is delivered to cells

• pulmonary ventilation
• external respiration
• internal respiration

exchange of gases between environment and lungs (alveoli) by breathing (inhalation and exhalation)

exchange of gases between lungs and blood (oxygen diffuses from alveoli to surrounding blood capillaries/carbon dioxide diffuses from surrounding blood capillaries to alveoli)

exchange of gases between blood and cells/tissues (oxygen diffuses from blood capillaries to body cells/carbon dioxide diffuses from body cells to blood capillaries)

use of oxygen by cell to catabolize nutrients and release energy; produces carbon dioxide as a waste

• nasal cavities
• pharynx
• larynx
• sinuses

• trachea
• bronchi
• lungs
• bronchioles
• alveoli

openings in the nasal cavity

cartilage tissue that divides nasal cavities

conchae

• receives air from nasal and oral cavity
• receives food and water from oral cavity

connects ears to pharynx

• nasopharynx
• oropharynx
• laryngopharynx

voice box

Adam's apple

opening between vocal cords that closes with swallowing

leaf-shaped cartilage that covers opening to larynx with swallowing, preventing food and liquids from entering respiratory tract

• small cavities in skull
• lined with mucous membrane
• lighten the weight of the skull
• give resonance quality to voice

sinus infection

forehead

behind cheek

between eyes

behind eyes

wind pipe

• primary bronchi
• secondary bronchi
• tertiary bronchi
• bronchioles terminal bronchioles

first two divisions at distal end of trachea that branch to enter each lung at notch called hilum

branch from primary bronchi to each lobe of lung

branch from secondary bronchi

branch from tertiary bronchi; no cartilage walls; have smooth muscle

branch from bronchioles

• air sacs at end of terminal bronchioles
• where diffusion of O2 and CO2 occurs
• produce surfactant

prevent collapse of alveoli

alveoli

• where gas diffusion takes place
• contain bronchi, bronchioles, and alveoli
• in thoracic cavity

two left lobes and three right lobes

the heart sits on the left side

separates thoracic and abdominal cavities

cavity between two pleural cavities that contain heart, large blood vessels, lymph nodes, esophagus, and trachea

mucosal and ciliated

blood accumulation in the pleural space

water accumulation in the pleural space

air accumulation in the pleural space

• inhalation/inspiration
• exhalation/expiration

inhalation/inspiration

• air is drawn into lungs
• diaphragm contracts and drops down towards abdominal cavity to enlarge thoracic cavity
• lung tissue expands
• internal and external intercostals contract pulling rib case up and out

exhalation/expiration

• air is expelled from the lungs
• diaphragm relaxes
• intercostals relax

gas required by cells for catabolism of nutrients and energy production that must be continually supplied by respiratory system

gas that is a waste product of cell metabolism that must be continually removed by respiratory system

carried towards body cells/tissues in blood (hemoglobin molecule on RBC)

carried away from the body cells/tissues in blood (hemoglobin molecule on RBC)

• involuntary control always overrides voluntary control
• chemoreceptors in carotid and aortic bodies respond to decreasing oxygen levels in circulating blood

Chemoreceptors near medulla respond to increasing carbon dioxide levels in circulating blood

• Chemoreceptors in carotid and aortic bodies respond to decreasing oxygen levels in circulating
• blood

medulla

cerebral cortex

• hyperventilation
• hypoventilation

• increased air enters alveoli as both rate and depth increases
• Lungs take in too much oxygen and eliminate too much carbon

decreased air enters alveoli

lungs take in too much oxygen and eliminate too much carbon dioxide making blood alkaline

Carbon dioxide builds up in blood making blood acidic

• infants (40+/min)
• children (20-40/min)
• adults (12-20/min)

listening to lungs with stethoscope (assesses breathing quality rather than rate)

rales, rhonchi, wheezing, stridor

abnormal musical sounds heard on inspiration; often called “crackles”

rattling sounds in bronchi due to obstruction or fluid; may be clear with coughing

whistling or musical sound heard during breathing that may indicate partially blocked or narrowed airway (asthma)

high pitched sound on inspiration

normal breathing

difficulty breathing (shortness of breath, painful or labored breathing)

difficulty breathing while lying down

temporary cessation of breathing

variation in breathing pattern with alternating periods of apnea and hyperventilation (critical illness)

decreased rate of breathing

increased rate of breathing (exercise/disease)

fluid or secretions coughed up from lungs

coughing up blood

lower than normal oxygen in arterial blood

lower than normal oxygen in tissues

bluish discoloration of skin, nails, or mucous membranes caused by not enough oxygen

cessation of respirations, often due to mechanical obstruction

total lack of oxygen

failure to resume breathing following period of apnea

group of tests that measure how well lungs inhale and exhale air/how efficiently lungs transfer gases (CO₂ and O₂) in blood

patient breathes into mouthpiece connected to instrument called spirometer; records amount and rate of air patient breathes in and out over a period of time