Week 4: pre-practical Flashcards
what does the respiratory system do?
it conducts air from outside the body to the gas exchange areas of the lungs (alveoli)
Oxygen is delivered to the blood for?
distribution.
the waste product, CO2, is taken up to the alveoli and eventually
expelled
the respiratory system consists of ?
upper and lower respiratory tracts
the upper respiratory tract consists of?
the nasal cavity, majority of the pharynx which connects nasal and oral cavity with larynx and esophagus
the lower respiratory tract consists of?
treachea, bronchi, terminal bronchi, respiratory bronchioles and alveoli
alveoli is the site of?
gas exchange, where O2 and CO2 enter and leave the lung capillaries
What is inspiration
breathing in, providing the alveoli with fresh atmospheric air
What is expiration?
breathing out, removing air containing decreased oxygen and increased CO2 concentrations
what is the name of the spaces within our skull that the nasal cavity is connected to?
paranasal sinuses
what is olfaction and what allows olfaction to occur
smell- which is promoted by olfactory nerves in the roof of the nasal cavity
the stem bronchi are clinically important as
inhaled particles can be trapped there
what is the purpose of conchae
they increase surface area, create turbulent airflow to increase olfaction and hide connections to sinuses & the orbit
In the lower respiratory tract, air is ___ ___ and ___
cleaned, warmed and humidified
the thoracic cavity contains
heart and lungs
the heart and lungs are both covered by
connective tissue sheets
What is the thoracic cage’s functions
it protects the organs with its joints and bones, and helps individuals participate in breathing
How does exhaled air coming out more slowly than normal in people with obstructive lung disease affect breathing?
Hyperinflation flattens the diaphragm which causes it to become less effective in regulating pleural pressures for efficient breathing
what is an example of an obstructive lung disease?
asthma
COPD is an umbrella term fro progressive lung diseases including
chronic bronchitis
emphysema
What is restrictive pulmonary disease?
when people cannot fully fill lungs with air- restriced from fully expanding
what is RPD caused by
pulmonary fibrosis, neuromuscular diseases, sarcoidosis which results in stiffness of lungs, chest wall, weak muscles and damaged nerves
chemoreceptors play a curcial role in monitoring what levels in the blood?
CO2, O2, pH
What is the role of central chemoreceptors?
- detect changes in pH of cerebrospinal fluid reflecting CO2 levels in blood
-detect an increase in CO2, lower pH, stimulating the repiratory centers to increase ventilation and expel CO2 as well as restore pH balance
what is the role of peripheral chemoreceptors?
- respond to low O2 levels (hypoxia) in arterial blood
- when O2 levels drop significantly, they signal the respiratory center to increase breathing rate and depth
During exercise, muscles require more __ and produce more __
O2 and CO2
when and why does increased ventilation rate and depth occur regarding exercise?
before exercise (due to anticipatory increase as a result of input from brain)
during exercise (increased CO2 and H+ stimulate chemoreceptors that lead to hyperventilation to expel CO2 and take in more O2)
How does neural control influence ventilation during exercise?
The movement of muscles and joints send signals to the brainstem from proprioceptors, stimulating ventilation
how is gas exchange optimised during exercise
more blood is directed to alveoli, with better oxygenation
how is there increased cardiac output during exercise?
the heart beats faster and pumps more blood to transport O2 efficiently to muscles
central chemoreceptors are the dominant?
driver of ventilation
Where are central chemoreceptors located?
inside the blood-brain barrier
CO2 diffuses easily through the blood brin barrier T or F
T
H+ travels easily through the blood brain barrier: T or F
F (travels with difficulty)
what are the name of 2 other receptors related to sensory input systems?
mechanoreceptors and metaboreceptors
what are the controls centre?
pons, medulla
Central chemoreceptors are predominatly located in the __ but also can be in other areas like the __
medulla, hypothalamus & cerebellum
Why do people die from opiods
causes depressing of nerve fibres and neurons, depresses breathing
what are the first 3 steps that occur during exercise?
- increased demand for oxygen in muscles
- increased production of CO2 in muscle
- stimulation of chemoreceptors surrounding muscle
what are the next 4, 5, 5 steps that occur during exercise
- increased PaCO2 and reduced PaO2
- stimulated peripheral and central chemoreceptors
- increased activity of phrenic and intercostal nerves
