The respiratory system Flashcards
What is the partial pressure of oxygen be…
Airways 149mmHg
Arteries 90mmHg
Veins 30mmHg
What is the partial pressure of carbon dioxide in blood?
Arteries 40mmHg
Veins 45mmHg
What should the oxygen saturation be in blood?
Arteries 100%
Blood 60%
What levels of bicarbonate should be in blood?
Arteries 24mEq/L
Veins 22mEq/L
What should the pH of blood be?
Arteries 7.4
Veins 7.35
What factors affect the rate and depth of breathing?
Chemoreceptors - detect changes in O2, Co2 and H+
Irritant
Stretch of lungs
Propioceptive - muscles and joints
What causes a greater simuliation for breathing than decreased oxygen?
Increased Carbon and Hydrogen
What defences do your respitory system have in place?
Nasal hairs, mucus layer, cilia, immune cells
What is the FVC
Forced vital capacity: This is the total forced amount of air on expiration possible by a person
What is the FEV1
Forced Expiratory Volume in 1 second:
This is the total amount of forced air out of a person’s lungs in the first second.
What should the FEV1 be?
It should be 70-80% of the FVC
What is the role of the respiratory system?
To transport oxygen and remove carbon dioxide in blood
What is needed for respiration?
A gas exchange membrane - diffusion
System of tubes - airways - trachea, bronchi, bronchiols
A bellows system - chest walls and muscles
Where are gases exchanged in the lungs?
Aveoli and capillaries
What effects the rate and depth of breathing?
levels of carbon dioxide, oxygen, and pH in the blood.
exercise, emotions, and respiratory diseases
What cells releases surfactant?
Type II
What holds the lungs open?
Negative intrapleural pressure
What is the main muscle used in breathing?
Diaphragm
What pulls the lungs back in?
Surface tension and elasticity
What reduces surface tension and makes breathing in easier?
Surfactant
What happens when the pressure in the pleural space increases?
The lungs will collapse
What system are the muslces of breathing controlled by?
Somatic system
What kind of muscles are used for respiration?
Smooth
Cardiac
Skeletal
Skeletal
The central chemoreceptors respond to?
Carbon and Hydrogen levels in the blood
The peripheral chemoreceptors respond to?
Hydrogen and Oxygen levels in the blood
What tissue is lung cancer most likely to arise from?
Epithelial
Air in the intrapleural space will:
Cause the lung to collapse
During an asthma attack:
ventilation is insufficient to allow enough gas exchange.
How does surfactant help to prevent the alveoli from collapsing?
It reduces the surface tension of alveolar fluid
How is most of the carbon dioxide in the blood transported?
As bicarbonate ions
Nasal breathing is preferred over breathing through the mouth because:
it allows warming and moistening of the inhaled air
Increasing the rate of breathing will:
decrease the partial pressure of carbon dioxide in the blood.
Ventilation is:
movement of air into and out of the lungs
What is the most powerful stimulus for altering the rate and depth of breathing in a healthy person?
Carbon dioxide in blood
What tissue type forms the alveolar wall through which gas exchange occurs?
squamous
When the diaphragm contracts the volume of the chest cavity:
increases
Which of the following is greatest? The partial pressure of carbon dioxide in:
arterial blood
venous blood
inspired air
in arterioles
What keeps the trachea open?
Cartilage
Why do most of the particles suspended in air fail to get down into the lungs?
Mucous and cilia
Blockage of pulmonary blood flow by a clot or similar obstruction is known as:
pulmonary embolism.
What do type II penuomcytes produce?
Surfactant
Air moves out of the lungs when the pressure inside the lungs is:
greater than the pressure in the atmosphere.
What does surfactant do?
decreases the surface tension in the aveolar fluid
Oxygen and carbon dioxide are exchanged at the lungs and at the cells by :
diffusion
Increasing the rate of breathing will decrease the partial pressure of what in the blood?
decrease the partial pressure of carbon dioxide in the blood.
What has negative pressure in the lungs?
The interpleural space
What stops the lungs from collapsing?
Surface tension and elasticity
Which part of breathing requires relaxation of muscles?
Expiration or breathing out
Which part of breathing requires contraction of muscles?
Inspiration or breathing in
If there is an increase of oxygen in the capillaries what happens in the tissues?
There is a decrease of oxygen in the tissues
How is oxygen transported?
It binds to haemoglobin
How is carbon dioxide transported?
