Thoracic cavity
location of lungs
Fancy word for nostrils
nares
Fancy word for nose hair
vibrissae
Pharynx
behind nasal cavity and back of mouth, where both air and food pass
Larynx
where only air passes, below pharynx
upper part of larynx
glottis
The larynx has the _____ that is covered during swallowing so that you don't choke
epiglottis
The larynx contains two _____ that are maneuvered using skeletal muscle and cartilage
vocal cords
From the larynx, air passes into the cartilaginous ______ and then into one of two ________.
trachea, bronchi
The bronchi divide into smaller structures known as _____.
bronchioles
Bronchioles branch into _____, where gas exchange occurs.
alveoli
Each alveolus is coated with ______, a detergent that keeps it from collapsing on itself
surfactant
Order of air passage
nares --> nasal cavity --> pharynx --> larynx --> trachea --> bronchi --> bronchiole --> alveoli
membranes known as ______ surround each lung
pleurae
a closed sac against which lungs expand
pleurae
the surface adjacent to the lung is the ________, and outer part is the _________, and the spare between this sac is the __________.
visceral pleura, parietal pleura, intrapleural space
lungs require ______ pressure for expansion
negative
diaphragm
a thin, muscular structure that divides the thoracic cavity from the abdominal cavity
external intercostal muscles _____ the thoracic cavity
expand
as the diaphragm flattens and the chest wall expands outwards, the intrathoracic volume __________
increases
an increase in the intrapleural volume leads to a ________ in intrapleural pressure
decrease
negative pressure breathing works by:
the chest cavity expands, the pressure in the lungs drops, and air rushes in from the higher pressure environment (outside).
is exhalation an active process?
no, it's passive. when the pressure in the lungs from deflation is higher than the outside world, then the air leaves.
During active tasks, inhalation and exhalation is sped up by using the ___________ muscles
internal intercostal muscles
spirometer
is an apparatus for measuring the volume of air inspired and expired by the lungs
Total lung capacity (TLC)
the maximum volume of air in the lungs when one inhales completely, usually 6 to 7 liters
Residual volume (RV)
the minimum volume of air left in the lungs when one exhales completely
Vital capacity (VC)
the difference between the minimum and maximum volume of air in the lungs (TLC minus RV)
Tidal Volume (TV)
The volume inhaled or exhaled in a normal breath
Expiratory Reserve Volume (ERV)
The amount of additional air that can be forcibly exhaled after a normal exhalation
Inspiratory Reserve Volume (IRV)
The volume of additional air that can be forcibly inhaled after a normal inhalation
Lung Volumes: Total lung capacity, tidal volume, inspiratory reserve volume, expiratory reserve volume, vital capacity, residual volume
ventilation center
breathing regulated by a collection of neurons in the medulla oblongata, regulate contraction of respiratory muscles
In the ventilation center, there are
chemoreceptors
that detect the levels of _______
CO2
As the partial pressure of CO2 rises in the blood, called
hypercarbia or hypercapnia
, the respiratory rate will ___________ so that the:
increase, CO2 levels decrease
hypoxia
low oxygen content in the blood
The walls of the alveoli are ____ cells thick
one-cell thick
The alveoli are for the diffusion of _____ and _____
CO2 and O2
Pulmonary veins
return oxygenated blood from the lungs to the left atrium
The driving force behind gas exchange in the alveoli is:
differences in pressure. Go down the concentration gradient, meaning CO2 diffuses down into the alveoli, and O2 diffuses out of the alveoli into the capillaries
How can the respiratory system be used for thermoregulation?
vasodilation and vasoconstriction
How are lungs involved in the immune system?
1) lined with mucous, vibrissae
2) contain lysozyme to attack gram-positive bacteria
3) cilia propel mucus upwards
4) mucociliary escalator
5) macrophage
6) mast cells: antibodies, hence allergies
Mucociliary escalator
cilia propel the mucus up the respiratory tract up to the oral cavity
Bicarbonate buffer system utilizes ________________
Le Chatelier's Principal