Respiratory Anatomy and Physiology Lab#5 Flashcards
What is the flow of blood controlled by?
Heart rate and blood pressure
How is breathing rate expressed?
Breaths/minute normally around 8-12 breaths per minute
What are the apices of the lung and where do they extend?
The apices are the corners of the tops of the lungs lateral to the heart.
What is the outermost surface of the chest cavity?
Thoracic well (rib cage, associated with its muscles)
What does the diaphragm create?
The inferior portion of the thoracic cavity
Does air pressure go from high to low?
Yes
What happens if tissues are deprived of oxygen for long periods of time?
They die
The lungs are individually surrounded by double membranous (serous membrane) sac called?
The pleura
What is one way to change pressure of a gas?
To change the volume of its container
How is the mechanical process of pulmonary ventilation achieved?
By rhythmically changing the volume of the thoracic cavity (Chest Cavity)
According to Boyle’s law changes in volume will change what in a a closed system?
The pressures
Pressures always flow from an area of ________ pressure to an area of ______ pressure.
High; Low
When the pressure inside the lungs drops slightly below atmospheric pressure as the chest cavity expands what happens to the air?
The air is drawn into the lungs
When the pressure in the lungs rises slightly above atmospheric pressure as the chest cavity relaxes what happens to the air?
The air is expelled out of the lungs
Inhalation is a mechanical process that involves what?
Enlarging the thoracic cavity
Movement requires ______ and ______ of skeletal muscles for contraction.
Energy and Innervation
What happens when the phrenic nerve innervates the the diaphragm?
It cause the dome-shaped muscle to flatten
The diaphragm is responsible for most of your breathing efforts when?
At rest
Intercostals are used to
Provide extra-inspiratory effort or for coughing when passive recoil of the lung does not provide enough expiratory force.
What happens when the external intercostal muscles contract?
They raise and pivot the ribs thereby lifting and expanding the outer walls of the thoracic cavity causing the volume of the thoracic cavity to be enlarged.
Once the volume of the lungs has increase what happens to the pressure inside the lungs?
It decreases
What is the intrapulmonary pressure?
About 3mmHg less than that of atmospheric air
Expiration is
Is usually a passive process that relies on the relaxation of skeletal muscles
If the diaphragm and intercostals return to their resting position what happens to the size of the thoracic cavity and the pressure in the lungs?
Thoracic cavity decreases and pressure increases
Emphysema is a disease caused by what?
Smoking and the inhalation of particulate matter
Is Emphysema preventable?
Yes
Emphysema destroys what?
The walls of the alveoli and the elastin in the lungs, both of which are important for passive exhalation.
What is the problem during the respiratory cycle for someone with Emphysema?
The blood is not being sufficiently saturated with O2 because the alveoli required for optimal oxygenation is of the blood have been destroyed.
The loss of elastin means the elasticity of the lungs are what?
Compromised and that the internal intercostals must be used to augment normal passive exhalation.
Asthma is
An obstructive lung disease where the flow of gas into and out of the lungs is compromised by a narrow airway.
Flow is proportional to what?
The radius to the 4th power
radius^4= air flow L/min
Airways can also become narrowed if
They become inflamed with and infection, and this can cause tissues lining the lumen to swell (obstructing airflow)
A 50% reduction in the radius of the tubes in a system will result in what?
In a 16 fold decrease in flow
Typically a person can forcibly exhale about what percent of their total lung volume in 1 second?
75-85%
FEV1 is
The forced expiratory volume in 1 second. From the top of IRV move one second to the right and where the line crosses the FEV line
Bigger the radius
More flow
More pressure gradient
The more blood flow
Spirometer records what?
Rate and depth of breathing
Speed of expiration
Rate of oxygen consumption
What produces variations in respiratory volumes?
A person’s size, sex, and physical condition
Minute ventilation is
The tidal volume multiplied by the frequency of breathing that was observed for one minute so it is the amount of gas moved through the respiratory system in a minute. example: 12breathspm*0.5L/breath=6.0L/minute
As the volume of a sealed container increases, the pressure of the gas inside the container does what?
Decreases
Is the pressure of the gas said to be proportional or inversely proportional to the size (volume) of the container?
Inversely proportional
What is Boyle’s law?
Pressure and volume of a gas have an inverse relationship, when temperature is held constant.
What enlarges the thoracic cavity?
Inhalation, a mechanical process
What nerve innervates the diaphragm, causing the dome-shaped muscle to flatten?
Phrenic nerve
Where does the phrenic nerve exit the brain and spinal column?
It exits the central nervous system (C3-C5) and travels to the diaphragm
What is responsible for most of your breathing efforts at rest?
Diaphragm
What is tidal volume? (TV)
The amount of air inhaled, or exhaled with each breath under resting conditions.
Breathing rate is typically about how many breaths per minute?
12 breaths/minute
What is the approximate TV for adult males and what is it for females?
About 0.5L
About 0.4L
What is respiratory rate?
How many times a minute a person takes in a breath.
What is the normal respiratory rate?
12-20 breaths/ minute
What is Minute Respiratory Volume (MRV)?
How much air a person moves in 1 minute.
Equation for MRV?
Respiratory rate X TV = MRV in L/min
What is inspiratory reserve volume? (IRV)
The amount of air that can be forcefully inhaled after a normal tidal volume inhalation.
What is the approximate IRV value for an adult male?
About 3L
What is expiratory reserve volume? (ERV)
The amount of air that can be forcefully exhaled after a normal tidal volume exhalation.
What is the approximate ERV value for an adult male?
About 1.2L
What is vital capacity? (VC)
The sum of the TV, IRV, and ERV
Equation for VC?
TV + IRV + ERV = VC in L
what is the normal VC for and adult male?
About 5L
What is residual volume?
The amount of air that is left in the lungs after the maximal exhalation.
What is FEV?
Volume of air blown out after full inspiration. From the top of the IRV peak to the bottom of the ERV valley.
Equation for FEV1 ratio?
FEV1/VC= % normal range is 75-85%
How much can a person typically forcibly exhale of their total lung capacity (vital capacity) in one second? also what is this called?
75-85%, FEV1
Blood is viscous (thickness) and air is not
True
What is the residual volume?
It is the amount of air that is left in the lungs after a maximal exhalation. WE do not fully empty out lungs with each breath. The volume of this air space is about 1000ml in the adult male 1L. therefore total lung capacity is 1.3L (residual volume) + 4.8L (vital capacity) = about 6 liter.
Residual Volume equation?
VC X 0.25 = RV
