Medic 14 A&P Chapter 15 notes

• Providing a large area fro gas exchange between air and circulating blood.
• Moving air to and from the gas exchange surfaces of the lungs 
• Protecting the respiratory surfaces from dehydration and temoerature changes and defending against invading pathogens 
• producing sounds that permit speech,singing, and non verbal auditory communication 
• providing olfactory sensations to the CNS for the sense of smell

• the nose (nasal cavity, and paranasal sinuses)
• Pharynx (throat)
• larynx(voicebox)
• trachea (windpipe)
• bronchi(conducing passageways)
• alveoli(exchage surfaces)

airways that carry air to and from the exchange surfaces of the lungs

• Conducting tract
• respiratory tract

entrance of nasal cavity to larger bronchi

smallest and most delicate bronchioles and alveoli

filter,warm, and humidify  the air, thereby protect he alveoli from debris ,pathogens,and enviromental extremes.

space enclosed with coarse hairs that extend across the tissue of the nostils and guard the nasal cavity from large airborne patricels

hyaline cartilage

respiratory mucosa

Is shared by the respiratory and digestive system

the internal nares ad the entrances of the esophagus

• nasopharynx
• oropharynx
• laryngopharynx

• connected to the nasal caivity by the internal nares and extends to the posterior edge of the soft palate
• lined with typical respiratory epithelium
• contains pharongeal tonsil and entrances to auditory tubes

• soft palate to the base of the tongue 
• palatine tonsils lie in the lateral walls

• extends between the level of the hyoid bone and entrance to the esophagus
• stratified squamous epithelium

Inhaled air leaves the pharynx and enters the larynx throguh the glottis

• voice box
• consists of 9 cartilages stabalized by ligaments, skeletal muscles or both

• epiglottis
• throid cartilage
• cricoid cartilage

• arytenoid 
• corniculate
• cuniform

• false vocal cords
• true vocal cords

the coughing relfex is activated

• begins at the 6th cervical vertebra where it attached to the cricoid cartilage 
• ends at the 5th thoratic vertebra in the mediastium

trachial cartilages that are c shaped

trachealis muscle, a band of smooth muscle

increases the diameter of the trachea

• Right/left primary bronchi to
• broncial tree 
• secondary bronchi (enter the lobes of lung)
• secondary bronchi  divide to form 9-10 tertiary bronchi in each lung

bronchiole

relaxation of the smooth muscles in the walls of bronchilses causing bronchodilation

broncoconstiction

supply air to a lobule of the lung

segment of lung tissue bounded by tissue partitions  supplied by a single bronchiole and accompanied by brancehs of pulmonary arteries and veins

openins at the ends of bronchioles

common chambers connected to multiple individual aveoli

thin simple squamous

phagocttize dust and debris in the lung

secrete surfactant onto aveolar surfaces

• lack of surfactant
• exhausing effort to inflating the deflated lung

• Pulmonary ventilation
• gas exchange
• gas transport

physical movement of air into and out of the lungs

involves gas diffusion at two sites: across the alveor air spaces and alveolar capillaries, and across the capillary cell membranes between blood and other tissue

involces transport of O2 and CO2 to and from alveolar capilaries and the capillary beds in other tissues

Oxygen staved tissues

oxygen supply cut off

• Inhalation(inspiration)
• Exhalation(expiration)

Aveolar ventilation

• Forms the flood of the thoracic cavity
•  dome shaped and projects upward into the thoratic cavity compressing the lungs

elevation of the rib cage increases the volume of the thoratic cavity whereas owereing decreases the volume

• indication of the lungs resilience and abilty to expand
• lower the complience the greater the force required to fill and empty the lungs

• quiet breathing
• forced breathing

• 75% Diaphragm
• 25% intercostals
• inhalation involves muscular contraction
• exhalation is passive

• Inhalation and exhalation are active
• involves accessory muscles during inhalation
• internal intercostals and abdominal muscles during exhalation

is the amount of air moved into or out of the lungs during a single respiratory cycle

• during a normal,quiet respiratory cucle under resting conditions the tidal volume averages 500 mL
• The amount that can be expelled at such a respiratory cycle is 1000 mL- ERV

• IRV is the ammount of air that can be taken in over and above the resting tidal volume
• 3300mL male vrs 1900mL female

the sum of the IRV and ERV

• is the ammount that remains in the lungs even after a maximal exhalation
• typicallt 1200 in male and 1100 in female

• chest cavity has been penetrated the ammount of air in the respiatory system is reduced to the minimal volume
• because surfactant prevents the collapse of aveolar surfaces

150 mL left over in passageways

• The partial pressures of the gases involved
• diffusion of molecules between a gas and a liquid

78.6%

20.9%

760 mmHg

• pressure contributed by a single gas
• and is abbreviated at P

• (N2) 597(78.6%)
• (O2) 159 (20.9%)
• (H2O) 3.7(0.5%)
• (CO2) 0.3 (0.04%)

• (N2) 573(75.4%)
• (O2) 100 (13.2%)
• (H2O) 47(6.2%)
• (CO2) 40 (5.2%)

• (N2) 569(74.8%)
• (O2) 116 (15.3%)
• (H2O) 47(6.2%)
• (CO2) 28 (3.7%)

• Internal 
• External

Diffusion between blood and interstital fluid across the endothelial cells of capillary walls

is the diffusion of gases between the blood and alveolar air across the respiratory membrane.

lower, higher

elevates the PO2 of Blood while lowering its PCO2

• 100 mmHg PO2
• 40 mmHg PCO2
• roughly

• 40 mmHg PO2
• 45 mmHg PCO2
• roughly

• PO2 
• pH
• Temperature

• dissolve in plasma
• bind to Hb within red blood cells
• be converted ti a molecule of carbonic acid H2CO3) All three process are completely reversable

bound O2

absorbed by peripheral cappillaries and transported as disolved gas molecules

23% CO2 transported this way

• 70% CO2 transported as bicarbonate ions
• molecules dissociate immediately into a hydrogen and a bicarbonate ion

CO2+H2O<------> H2CO3 <-->H+ + HC)-3

CO2+H2O<---> H+ HCO-3

Mass movement of chloride Ions into RBC

Matched

identical

• Changes in blood flow and oxygen delivery under local control
• Changes in the depth and rate of respiration under the control of the brain's respiratory centers

intersitial PO2 falls and PCO2 rises

carried away

smooth muscles in the walls of arterioles in the area, which increases blood flow

bronchioles dilate

bronchiles constrict

• Meulla oblongata and the pons
• regulate the respiratory muscles and control the frequency and depth of breathing

cerebral cortex

nuclei in the reticular formation of the pons and medulla oblongata

set the pace for respiration

• Dorsal respiratory group ,insiratory center
• Ventral respiratory group, expiratory group

every respiratory cycle

gradually increase stimulation of the inspiratory muscles, for two seconds and then inspiratory center becumse silent for next three seconds

• forced breathing
• when it activates the acessory muscles involved in ihalation and exhalation

• mechanoreceptors (baro and stretch)
• chemoreceptors

respiratory reflexes

changes in volume in lungs andchanges in arterial blood pressure

prevents lungs from overexpanding

inhibits the expiratory center and stimulates the inspiratory center when lungs are collapsing

hering breuer reflexes

pH