Ch 22: Respiratory System Flashcards
The main function of the respiratory system is
ventilation of the lungs to acquire O2 expel CO2
What are the other 8 functions of the respiratory system?
- Gas exchange
- Communication
- Olfaction
- Blood acid/base balance
- Blood pressure regulation
- Blood and Lymph circulatioin
- Blood filtration
- Expulsion of abdominal content
Blood acid-base balance is regulated by
the exchange of O2 and CO2
How does the respiratory system help with blood and lymph circulation?
The rhythmic contraction and relaxation of the diaphragm helps circulate them.
How does the respiratory system help with expulsion of abdominal content?
Taking a breath before urination, defication or regurgitation increses internal pressure assisting in expulsion effort
What are the two zones of the respiratory system?
Briefly explain each.
- Conducting zone: system of tubes that allows for the passage/direction of air.
- Respiratory zone: the part responsible for gas exchange
What are the main parts of the respiratory system anatomy?
- Nose
- Pharynx
- Larynx
- Trachea
- Bronchial tree
- Lung
The respiratory system is located in what cavity?
What other major organ is in this cavity?
- Pleural cavity
- The heart
The nasal cavity is lined with
respiratory and olfactiory epithelium
Both epithelium of the nasal cavity are _______.
pseudostratified ciliated
What dles the respiratory epithelium do to the air coming in?
Warms it
What are the characteristics of the olfactory epithelium in the nasal cavity?
- Contain odor binding proteins on cillia
- Proteins are attached to sensory neurons
- Provides sense of smell
The pharynx stretches from the _______ to the _______.
nasal cavity, larynx
What are the three parts of the Pharynx?
- Nasopharynx
- Oropharynx
- Laryngopharynx
What are the characteristics of the nasopharynx?
- Sits above soft palate
- Eustachian tube (middle ear) enters here
- Pharyngeal tonsils are located here
Where is the oropharynx?
It is the space between the soft palate and epiglottis
What are the characteristics of the laryngopharynx?
- Posterior to larynx
- combines with mouth
- passes both air and food
- lined with stratified squamous epithelium
- leads to both larynx and esophagus
What prevents food from going down the trachea? Where is it found?
- Epiglottis
- It is found in the laryngopharyx
Where are the vocal chords found?
How do the work?
- Larynx
- Air passes over the vocal cords to create sound
Why does the trachea have cartilage rings?
To ensure that the trachea stays open to allow for the passage of air
The bronchial tree consists of…
- Trachea
- Main bronchi
- Secondary bronchi
- Brioncoles
What is the main difference between bronchi and broncioles?
Broncioles don’t have cartilage so they have the ability to expand and contract.
Bronchioles form into _______ which end in _______.
Terminal bronchioles, alveoli
Everything prior to the terminal bronchioles is considered part of the _______.
conducting zone
The lungs are a collection of…
bronchioles and alveoli
Terminal bronchioles and alveoli are part of the _______.
Respiratory Zone
What are the characteristics of the Alveoli?
- site of gas exchange
- compeltely covered with capillaries
- alveoli/cappillaries are the interface that allows for gas exchange
- Composed of three different types of cells
What 3 types of cells are found in the alveoli?
Briefly describe each.
- Simple Squamous (type 1): line air sac, allow for diffusion
- Great alveolar cells (type 2): cuboidal cells that secrete a substance called surfactant
- Alveolai Macrophage: Phagocytotic cells that engulf debris
Surfactant is a combination of…
phospholipids and proteins that coat alveolar walls and reduce surface tension
The lungs are encased within the
Pleural cavity
What are the three parts that make up the serous membrane that surrounds the lungs?
Briefly describe each.
- Parietal pleura: the OUTER layer
- Visceral pleural: The INNER layer
- Pleural fluid: fluid that is between the parietal and visceral pleural layers. Prevents friction
The pleural cavity is air tight with one exception…
one opening to allow for the trachea to pass through
The parietal cavity being air tight allows for the creation of a _______ to be formed.
pressure gradient
The three main physiological events are…
- Ventilation
- Gas exchange
- Transport
External ventilation occurs at the _______ where as internal ventilation occurs at the _______.
alveoli, tissues
Inhaling and exhaling is known as the
Cycle of inspiration
Normal involuntary breathing is called
quiet breathing
Conscious voluntary breathing is know as
forced breathing
What are the charaterisitics of the diaphragm?
- large flat muscle
- separates thoracic and abdominal cavities
- primary muscle of breathing
What are the three respiratory muscles?
- Diaphragm
- Intercostal
- Abdominal
The process of breathing depends on what 3 factors?
- Pressure
- Air flow
- Resistance
Air pressure at sea level (1 atm) = _______ mmHg
760
What is Boyle’s Law?
The volume of gas is inversely proportional to pressure.
Pleural Cavity
Increase of volume = _______ of pressure.
Decrease
Pleural Cavity
Decrease of volume = _______ of pressure.
Increase
Air flows from _______ pressure to _______ pressure.
High, Low
When relaxed, lung pressure and atmospheric pressure…
are equal.
True or False
Inhalation is a passive process.
False.
Inhalation requires energy to contract muscles
True or False
Exhalation is an active process.
False.
Muscles are relaxing at this stage and require no energy.
Why does air flow into the lungs when breathing.
The expansion of the chest causes an internal pressure that is less than the atmospheric pressure, so air follows gas laws and flows from high pressure to low pressure.
Why does air flow out of the lungs during exhalation?
Because the volume of the lungs is decreasing creating pressure that is greater than atmospheric pressure. Following gas laws, air flows from the high pressure of the lungs to the lower pressure of atmosphere.
When the diaphragm flattens out, is it contracting or relaxing?
Contracting
Resistance _______ air flow.
slows
What two factors effect resistance of air flow in the lungs?
- Diameter of bronchioles
- Pulmonary compliance
Bronchiodilation _______ air flow because there is _______ resistance.
increases, less
Bronchioconstriction _______ air flow because there is _______ resistance.
decreases, more
Epinephrine and the sympathetic nervous system ______ air flow.
speed up
The parasypathetic nervous stystem will _______ air flow.
slow down
What is meant by “Pulmonary compliance”?
The ability of your lungs to expand
True or False
Lung disease effects pulmonary compliance.
True.
The fluid film between alveoli and bronchioles has _______ that can prevent alveoli and lung expansion.
surface tension
What chemical do alveoli secrete that breaks down fluid film surface tension between alveoli and bronchioles?
Surfactant
Regulation of breathing is under _______ control.
neural
Specifically the _______ of the brain stem contains the breathing centers of the brain.
Medulla oblongata
Neural Breathing Receptors
What do central chemo-receptors do and where are they found?
They detect pH levels in blood and are found in the medulla oblongata.
Neural Breathing Receptors
What do peripheral chemo-receptors do and where are they found?
The detect O2 and CO2 levels and are found mostly in the carotid artery and aorta.
Neural Breathing Receptors
What do stretch-receptors do and where are they found?
Detect the volume of air and are found in the bronchioles.
Neural Breathing Receptors
What do central irratant-receptors do and where are they found?
Detect particles and cause coughing. They are found in the epithelium of airways.
What is forced breathing used for and what is it controlled by?
It is used in speech, blowing, singing, pranayama, etc and is controlled by the cerebral cortex.
What is Dalton’s Law?
That atmospheric pressure is the sum of all it’s component partial pressures
What is the math formula for partial pressure?
percentage of gas * ATM = Partial Pressure
Atmosphere is composed of
__% Nitrogen
__% Oxygen
__% Carbon Dioxide
- 6% Nitrogen
- 9% Oxygen
- 04% Carbon Dioxide
In extrernal respiration at the alveoli, O2 moves into _______ while CO2 moves into _______.
capillaries, alveoli
Gasses move according to pressure _______.
gradient
Preassure gradient refers to
the partial pressures of the components of a gas.
Diffusion relies on _______ as well as _______.
partial pressure gradient, solubility
Solubilitiy is the ability of a gas to
dissolve in the fluid interface.
What is Henry’s Law?
The amount of gas that dissolves in H2O depends on partial pressure and solubility.
When blood enters the lungs from the pulmonary arteries, what are the partial pressures of oxygen and carbon dioxide?
O2 = 40mmHg
CO2 = 46mmHg
Explain O2 transfer at the alveoli during inhalation
- O2 in alveoli has a partial pressure of 158 mmHg, while the partial pressure of O2 in the blood vessels is 40 mmHg.
- Following gas/partial pressure laws, O2 will diffuse from the higher O2 pressure in alveoli into the lower O2 pressure in the blood vessels, thus oxygenating the blood.
Explain CO2 transfer at the alveoli during inhalation
- CO2 in alveloi has a partial pressure of .3 mmHg, while the partial pressure of CO2 in the blood vessel is 46 mmhg.
- Following gas/partial pressure laws, CO2 will diffuse from the higher pressure in blood to the lower pressure in the alveoli, thus eliminating CO2 from the blood.
Given the pressure differences in O2 (higher) and CO2 (lower), why is the transfer rate in diffusion during inhalation basically the same?
Because CO2 is 20% more soluble than O2
What three other factors can effect rate of gas exchange?
- Membrane thickness
- Membrane Area
- Ventilation perfusion coupling
How does membrane thickness effect diffusion?
What is a cause of membrane thickening?
- The thickened membrane takes longer to get through, thus slows diffusion.
- Smoking
How does membrane area effect diffusion?
Give an example of something that would adversely effect membrane area.
- A smaller area can’t diffuse as much as a larger area.
- Emphysema destroys lung tissue, thus lessens area
What does ventilation coupling refer to?
- Ventilation is the bringing in of air
- Perfusion is the bringing in of blood
- Coupling refers to doing both in unison
How are ventilation and perfusion rates unified/coupled in gas exchange?
Why is it important?
- Bronchioles and arterioles will constrict/dilate together to ventilate and perfuse together
- Doing so ensures the efficency of gas exchange
What is meant by gas transport?
The movement of gases throughout the body using the circulatory system.
Why doesn’t O2 break down during transport?
It has a low solubility rate, thus resists dissolution in blood plasma
How is O2 transported throughout the body?
By bonding to the heme in hemoglobin within red blood cells.
How many O2 molecules can bind to one heme in an RBC?
4
How many heme are in a protein of hemoglobin?
4
Explain the process of O2 binding to heme.
- iron first binds to heme
- O2 then binds to the iron
- The binding is cooperative
What is meant by the binding of O2 is cooperative?
- The binding of the first makes it easier for the second to bind
- The binding of the second makes it easier for the third, etc up to 4 per heme.
- This process acts like a magnet for O2
In what three ways is CO2 transported throughout the body?
- By dissolving in plasma
2.
What is the danger in CO2 combininb with water and becoming carbonic acid?
- Carbonic dissociates into hydrogen and bicarbonate ions.
- Hydrogen determines blood pH (raises acidity and lowers pH)
Systemic Gas Exchange occurs at
tissues around the body
Gas exchange at the tissue level is called…
internal respiration
In internal respiration, what is occuring with O2 and CO2?
O2 is being delivered to feed tissues and CO2 waste built up from tissue use is picked up to be excreted.
O2 and CO2 loading and unloading in internal resperation happens through _______ and is driven by _______.
diffusion, partial pressure laws
What is the venous reserve?
- Some O2 remains bondied to hemoglobin after unloading and can be used for tissues on the way back to the heart.
Quiet respiration has a _______ based on blood gases.
rhythm
Normal blood has an oxygen a partial pressure of __ mmHg. Carbon dioxide has a partial pressure of __ mmHg. And normal blood pH is __.
oxygen = 95 mmHg
carbon dioxide = 40 mmHg
pH = 7.4
_______ keeps O2 and CO2 partial pressures and pH relatively stable.
Breathing
True or False
Oxygen plays a large role in breathing rate.
False.
Its all about the CO2
When would oxygen actually play a large role in breathing rate?
In high elevations where oxygen levels are low.
What are two types of respiratory disorders?
- Hypoxia
- Chronic Obstructive Pulmonary Disease (COPD)
What is hypoxia?
Insufficient oxygen levels
What are the four types of hypoxia?
Briefly explain each.
- Hopoxemia: low arterial partial pressure of O2
- Ischemic: heart failure
- Anemic: RBCs don’t carry enough O2
- Histoxic: metabolic problems, poisons (like cyanide) interfere with cellular respiration
What is COPD?
Any kind of long lasting obstruction to respiratory function
Give two examples of COPD with brief explanation.
- Chronic bronchitis: inflammation of bronchi which decreases ventilation
- Emphysema: distruction of lung tissue, lowering surface area, deacreasing gas exchange.
