Respiratory system Flashcards
7 functions of respiratory system
o Ventilation- moves air
o Gas exchange
o Pressure changes in thoracic cavity helps with venous return and helps expel contents from abdominopelvic cavity
o Olfaction
o Speech and sound
o Regulates blood volume by pushing on the veins and moving blood through
o Regulates blood ph by eliminating CO2
upper respiratory system
nose, nasal cavity, paranasal sinuses, pharynx, larynx. Filters warms and humidifies incoming air
lower respiratory system
trachea, bronchi, bronchioles, alveoli of lungs, more delicate surfaces. Has more smooth muscle so can constrict.
conducting zone
from entrance of the nasal cavity through the airways to the terminal bronchioles. moves air to the lungs and allows air to reach exchange surfaces. Controls air flow, traps pollutants
respiratory zone
respiratory bronchioles, alveolar, alveoli, exchanges between air and blood takes place
Mucosa
lines the conducting portion of respiratory tract = lamina propria + epithelial cells
what are mucous glands for and where are they found
for defense and mostly in the upper conducting portion
what is smooth muscle for and where are they?
smooth muscle for regulatory control mostly in the lower conducting portion.
what is mucous made by and for what purpose
mucus is made by goblet cells and mucous glands and traps pollutants and pathogens.
cilia function
to move mucous towards the pharynx where it is swallowed
consequence if cilia destroyed
caused by smoking and they cough more to expel mucous
cilia location
lining the trachea
nasal conchae function
splits air into separate streams
function of hairs
trap large particles
vascularization of respiratory system
regulates temperature, mucus traps particles and humidifies incoming air
olfactory receptors
smell
3 types of pharynx
nasopharynx (back of nose), oropharynx (back of mouth), and laryngopharynx (lower end of the pharynx)
larynx
voice box- the hollow muscular organ forming an air passage to the lungs and holding the vocal cords
glottis
narrow opening at superior end of larynx
pharynx
throat- shared by both resp. and digestive system
epiglottis
lid, which covers glottis when swallowing so food does not go into lungs
phonation
sound from voice
what determines pitch of voice
pitch based on diameter and how stretch. more stretched=higher pitch, thicker strings=deeper voice
what determines volume of voice
how much air
Articulation
production of speech
what is important for articulation
amplification and lip and tongue movement
trachea
windpipe. cartilaginous tube that connects the pharynx and larynx to the lungs. shaped like the letter C. an opening to the back
trachealis muscles
can expand the esophagus to accommodate big amounts of food
bronchitis
results in inflamed, constricted bronchi
bronchioles
smallest airway
bronchioles structure
no cartilage, no mucous, few cilia, lined with smooth muscle
how sympathetic and parasympathetic effect the bronchioles
sympathetic: bronchodilation and parasympathetic: bronchoconstriction
Lungs structure
3 lobes in right, 2 lobes in left right is a little larger, left needs to accommodate for heart
pleurae of lungs
visceral: on lung and parietal: on wall of thoracic cavity
Type I cells
simple squamous epithelium which makes 90% of the wall of alveolus
type 2 cells
cells which produce surfactant
surfactant
a fatty mixture, which coats the lumen of the alveoli, reduces surface tension and keeps alveoli open
alveolar macrophages
mobile phagocytes which engulf small particles trapped in bronchioles or alveolar surfaces
3 parts of respiratory membrane
o Squamous epithelial of alveolus – type 1 cells
o Endothelial cells of capillary -
o Basal lamina: in between squamous epithelial and endothelial cells
What happens in pneumonia and why it impairs gas diffusion
inflammation of the lobules of lungs which makes it harder for diffusion of gases and to oxygenate lungs/blood
Pulmonary circulation
portion of the circulatory system which carries deoxygenated blood away from the right ventricle of the heart, to the lungs, and returns oxygenated blood to the left atrium and ventricle of the heart.
pressure of pulmonary circulation
has low pressure because of the extensive capillary beds in the lungs and less pressure generated by RV
brachial tree
the branching system of bronchi and bronchioles conducting air from the windpipe into the lungs.
primary bronchi
branch off of trachea to lungs
secondary bronchi
one to each lobe, three on right and two on left
tertiary bronchi
less cartilage, more smooth muscle as bronchi branch and get smaller
terminal bronchioles
last generation of conducting zone airways
Respiratory bronchioles
identified by the presence of some alveoli along their walls
pulmonary ventilation
movement of air in and out of lungs
gas exchange
pulmonary and tissue gas exchange. Movement of gases between lungs and blood
gas transport
movement of gases through blood
Atmospheric pressure
pressure by the weight of the atmosphere, at sea level atmospheric pressure = 760 mm Hg. As you go to higher altitudes AP goes down and there is less pressure
intrapulmonary pressure
pressure inside lungs (inside aveoli)
intrapleural pressure
pressure between pleurae (outside of the lungs). Relative vacuum (always lower than atmospheric pressure and intrapulmonary pressure)
Boyle’s law
P = 1/V. As volume increases pressure decreases. As volume decreases pressure increases
standard atmospheric pressure
760 mm Hg
Factors that influence resistance to airflow:
airway resistance, surface tension, and compliance
airway resistance
anything that impedes air flow through respiratory tract
role of dilation, constriction, and blockage on breath
dilation: easier to breath, constriction: harder to breath and blockage: increase resistance and makes it difficult to breath
surface tension
reduced by surfactant
compliance
measure how easy it is to expand the lungs
what can cause increased compliance
emphysema: individual alveoli get destroyed and makes it harder to exchange oxygen
what can cause decreased compliance
broken rib, no surfactant, scar tissue
pneumothorax
if intrapleural pressure becomes equal or higher than atmospheric pressure, it no longer exerts suction effect that prevents lungs from collapsing. The added pressure makes lungs immediately collapse. Usually from puncture to lungs
Restrictive lung disease
decrease pulmonary compliance (fibrosis, neuromuscular disease)
obstructive lung diseases
increase airway resistance. Easier to breath in than breath out. Trap oxygen poor, carbon dioxide rich air in airways (emphysema, bronchitis, asthma)
Definition of respiratory rate
breaths per minute
tidal volume
air moved during one respiratory cycle
respiratory minute volume
amount of air moved per minute
= TV x RR
Anatomic dead space
air volume in conducting airways
alveolar ventilation
amount of air that reaches the alveoli in a minute
ERV
amount of air that can be forcefully exhaled after normal exhalation
residual volume
air that remains in lungs after maximal exhalation
IRV
amount of air that can forcefully be inhaled above tidal volume
Inspiratory capacity
the total amount of sir that can be inhaled
Functional residual capacity
the amount of air left in lungs after a quiet exhalation
vital capacity
the maximal amount of air that can be moved in and out of the lungs
total lung capacity
total volume of the lungs (all four volumes together).
how to calculate respiratory minute volume
RR x TV
how to calculate alveolar ventilation
RR x (TV – Vd)
AV depends on what?
RR and TV, because Vd does not really change
how to calculate vital capacity
ERV + TV + IRV
how to calculate total lung capacity
TV + ERV + IRV + RV
Dalton’s law
each gas in a mixture exerts its own pressure called partial pressure relative to its abundance. The total pressure of a gas mixture is the sum of the partial pressures of all of its component gases.
partial pressure
how much of a gas there is
What happens to oxygen partial pressure at higher altitudes
it decreases
Partial pressure of oxygen in alveoli
104 mmHg
Partial pressure of CO2 in alveoli
40 mmHg
Henrys law
higher partial pressure means more dissolved gas; lower partial pressure the less dissolved gas
the amount of gas dissolved depends on
solubility (CO2 has better solubility then O2)
the 5 factors that determine efficiency of gas exchange
Difference in partial pressure – bigger gradient difference will give you more diffusion Distance for diffusion Lipid solubility of gasses Total surface area for diffusion Respiration-perfusion matching
to get better gas exchange you need
bigger pressure gradient small distance for diffusion good lipid solubility large surface area for diffusion (more alveoli) good respiration perfusion matching
Carbon dioxide transport in blood
o Dissolved in plasma
o Bound to protein portion of Hb
formula how CO2 is converted to carbonic acid and from there to H+ and bicarbonate
CO2 + H2O – H2CO3 — H+ + HCO3-
What happens to each product of the CO2 and H2O reaction?
Hydrogen binds to hemoglobin, and bicarbonate leaves the red blood cell and dissolves in plasma
carbonic anhydrase
turns CO2 and water into H2CO3 (carbonic acid)
voluntary vs involuntary control of respiration
Voluntary: make decision to hold breath or breath and involuntary neural control: in the medulla oblongata and is stronger than voluntary
Role of RRG
all neurons involved in creating basic rhythm for breathing in the medulla oblongata
VRG
involved in control of muscles for inspiration and expiration
DRG
involved in control of inspiration and processing of sensory input
How chemoreceptors work
balance respiratory rates. Triggered by low oxygen and high CO2
what is hypercapnia
triggers hyperventilation
hypocapnia
triggers hypoventilation
Effect of baroreceptor reflex on breathing
speed up breathing and raise blood pressure
Hering-Breuer reflex
stretch receptors in lungs and prevents them from over expanding or under inflating
Protective reflexes
sigh, yawn, cough, sneeze
Other factors that affect breathing
stress, pain, change in temp, swallowing…
respiration-perfusion matching
blood goes to where fresh air is and air goes to where the blood is
Vestibular folds
close off glottis during swallowing and play no role in sound production
how do vocal folds work
“vocal cords” vibrate to make sound.
alveoli
ends of respiratory trees within alveolar sacs. Sites of gas exchange
