Respiratory System: Anatomy
Function: to remove [particles from air & transport it into the body
to the lungs
Respiration: exchange of gases between atmosphere & body cells
1. breathing: pulmonary ventilation – movement of air in/out of
lungs
2. exchange of gases between lungs & blood
3. transport gases by blood w/ lung & body cells
4. cellular respiration: utilization of oxygen & production of
carbon dioxide
ORGANS of Respiration
I. Upper: outside the thorax
II. Lower: within the thorax
I.
Upper Respiratory Organs
1. Nose: supported by bone & cartilage, two nostrils to allow air to
enter nasal cavity guarded by internal hairs to prevent large
particles from entering
2. Nasal Cavity: hollow space behind nose, divided into R & L
portions by nasal septum ( made of cartilage & bone)
Nasal conchae- support the mucous membrane that lines the nasal
cavity & help to increase surface area
Function: to moisten air & sticky mucus to trap & filter particles,
network of blood vessels, to heat & warm air
3. Paranasal sinus: air filled spaces in skull to help reduce weight of
skull & resonance of vocal sounds
4. Pharynx (throat) between nasal cavity & larynx.
Functions: passageway for food into oral cavity to esophagus & air
traveling between nasal cavity & larynx, also aids in producing sound
for speech
5. Larynx (voice box) enlargement (Adam’s apple- thyroid cartilage)
in airway at top of trachea below pharynx, elastic cartilage around
epiglottis to be flexible
Functions: move air in/out of trachea, prevent foreign objects in
trachea (switching mechanism: allows food =esophagus
air=trachea), houses vocal cords (2 pairs)
a. false vocal cords: upper fold, no function in sound production,
close airway during swallowing
b. true vocal cords: folds to make vocal sounds, air forced
between cords causing vibrations
quality of sound based on shape of larynx, pharynx & oral cavity,
pitch (muscle tone)change in the tension of vocal cords, intensity
(loudness) forces of the air thru v.c.
Glottis-opening between vocal cords
Epiglottis- air enters larynx, during swallowing larynx raised,
epiglottis closed prevent food into air passageway
II. Lower Respiratory Organs
6.Trachea (windpipe) flexible tube, 12.5 cm into thoracic cavity, front
of esophagus, splits into R/L bronchi
Lined w/ ciliated mucus membrane to help remove particles
20 ‘C’ (open ring) shaped hyaline cartilage pieces, to prevent trachea
from collapsing & blocking airway, soft tissue in back of ‘C’ expands
as food passed thru esophagus
7. Bronchial Tree: branches from trachea to air sacs
A. primary bronchi- R/L from trachea at 5th thoracic vert.
8. Bronchioles- finer, smaller tubes, no cartilage, increased smooth
muscle
Both serve as air passages, help remove particles
10.
Alveolar ducts- thin tubes
B. Alveoli- lg surface area, capillary/cell net, exchange gas
9. Lungs: cone shaped organs in thoracic cavity, separated by heart
& mediastinum, occupies most of thoracic space, suspended by
bronchi
a. visceral pleura-attached to surface of lung
b. parietal pleura- lines inner wall of thoracic cavity
c. pleural cavity-space between the 2, lubricates to reduce friction
during breathing
right lung larger- 3 lobes, left lung –2 lobes
each lung includes air passages, alveoli, blood vessels, lymphatic tissue
& nerves