Respiration Flashcards
What are the functions of the Respiratory System
- Provides extensive gas exchange, surface area between air & circulating blood
- Regulation of blood pH = Blow off CO2
- Voice production = when we exhale
- Olfaction = sense of smell
- Protection
Respiration
Sequence of events that result in the exchange of O2 & CO2 between the external environment & mitochondria
External Respiration
Gas exchange @ the respiration surface
Internal Respiration
Gas exchange @ the tissues
Mitochondrial Respiration
Production of ATP via oxidation of carbohydrates, amino acids, or fatty acids (O2 consumed & CO2 is produced)
What are the functions of the Pulmonary Alveoli
Site of Gas Exchange
- Expand in Inhalation (O2 in)
- Shrink in Exhalation (CO2 out)
- Consists of simple squamous epithelium = Thin
What are the properties of Lungs
Compliance = Distensibility (stretchability) = How lungs expand, affected by surfactant. Mammalian Lungs easily expand = high compliance
Elasticity = Tendency to return to initial size after distension. Recoil ability (destroyed by smoking)
What is Boyle’s Law
Boyle’s Law = pressure of gas in a closed container is inversely proportional to the volume of the container
Increase volume = Decrease pressure
What are the cells of the alveoli? What are their functions
- Consist of thin, delicate pneumocytes Type 1 = gas exchange
- Consist of pneumocytes Type 2 = produce surfactants
- Patrolled by alveolar macrophages (Dust Cells) = clean off particles (dust of microorganisms)
What is the function of surfactants?
How do they affect compliance?
Surfactants = Decrease the work of breathing
- Surfactants reduce surface tension of H2O
- Makes it easier to inhale -> increase compliance
Compliance = the measure of the lungs ability to stretch & expand
How is O2 transported? What is the importance of hemoglobin?
- O2 transported by carriers.
PO2 (partial pressure of O2) is low in blood = improved O2 extraction - O2 binds reversibly to hemoglobin
Hemoglobin (Hb) = metalloproteins
What are the effects of pH on O2 affinity
HIGH pH = Less O2 is released (Curve shifts to left / lower) = More Affinity lets go of O2 later
LOW pH = More O2 is released (Curve shifts to right / higher) = Less Affinity lets go of O2 sooner
What are the effects of CO2 on O2 affinity
HIGH CO2 = More O2 is released (curve shift right / higher) = Less Affinity lets go of O2 sooner
LOW CO2 = Less O2 is released (curve shift left / lower) = More Affinity lets of of O2 later
What are the effects of Temperature on O2 affinity
HIGH Temp = More O2 is released (curve shift right / higher) = Less Affinity lets go of O2 sooner
LOW Temp = Less O2 is released (curve shift left / lower) = More Affinity lets go of O2 later
What is diphosphoglycerate? Where is it produced? When is it produced?
Diphosphoglycerate = By product of RBC activity = make ATP by anaerobic mechanism
= Produce DPG as a byproduct = always
How is CO2 transported in blood?
What is the importance of carbonic anhydrase
Carbonic Anhydrase = an enzyme that catalyzes the formation of HCO3 from CO2
CO2 + H2O <=> H2CO3 <=> HCO3 + H+
What does the Fick equation explain
Fick equation = Fick equation gives the rate of diffusion. How gases move down pressure gradients
J = DAdC/dx
Why is Henry’s Law important? What does it allow you to measure?
Henry’s Law: Gas = Pressure x Solubility
How gases dissolve before they diffuse -> must get into blood
- gas under pressure with liquid, the gas dissolves in liquid until equilibrium is reached.
@ given temp. gas in solution = partial pressure of gas
Describe the different solubility’s of CO2 & O2. Why do they matter?
CO2 likes H2O = High Solubility (diffuses faster than O2 in water)
O2 does NOT like H2O = Lower Solubility than CO2 (diffuses the same as CO2 in air. x1.2)
@ same pressure, CO2 has a much higher solubility in H2O than O2. Had to evolve a mechanism to carry more O2 & must blow off CO2
What is Hypoventilation?
Hypoventilation = Abnormally low respiration rate
-> results in CO2 buildup in blood (High PCO2)
- Hypercapnia
What is Hyperventilation?
Hyperventilation = Abnormally High respiration rate
-> results in Low PCO2
- Hypocapnia
Acidosis v.s. Alkalosis
Acidosis: Low Plasma pH = High H+
Alkalosis: High Plasma pH = Low H+
Define Metabolic Acidosis. What are some causes? How can it be fixed?
Metabolic Acidosis: Low pH = High H+
CO2 +H2O <- H2CO3 <- HCO3 + **H+ ** ( = increase)
Causes :
- Proton accumulation, Ketoacids (from breakdown of fats or amino acids), kidney diseases -> if kidney can’t pee out H+
Fixes :
- Hyperventilate (combine the H+ w/HCO3 & make the CO2 to blow off)
- Renal (kidneys) compensation (pee out H+ Keeps HCO3)
Define Respiratory Acidosis. What are some causes? How can it be fixed?
Respiratory Acidosis: Low pH = High CO2
Lungs are mucked up = Cant exhale enough CO2 = causes hypoventilation
CO2 +H2O -> H2CO3 -> HCO3 + H+ ( = increase)
Causes :
- Hypoventilation which could be due to a wet lung (pneumonia), some obstruction in respiratory system
(any disease that prevents CO2 fro being exhaled.
Bronchitis = lots of mucous. Pulmonary edema)
Fixes :
- Renal (kidneys) compensation (pee out H+ & keep HCO3)
Define Metabolic Alkalosis What are some causes? How can it be fixed?
Metabolic Alkalosis: High pH = Low H+
CO2 +H2O -> H2CO3 -> HCO3 + H+ (decrease)
Causes :
- Loss of protons due to vomiting, diarrhea (Loss HCl)
Fixes :
- Hypoventilate = keep in CO2 to make H+, breathe less to keep CO2 & then make H+
- Renal (kidneys) compensation (keep in H+)
- Alkaline tides = increase in pH after eating large meal
Define Respiratory Alkalosis. What are some causes? How can it be fixed?
Respiratory Alkalosis: High pH = Low CO2
CO2 +H2O -> H2CO3 -> HCO3 + H+ (decrease)
Causes :
Hyperventilation = blowing off too much CO2 = panic attack, high altitudes
Fixes :
Renal (kidneys) compensation (keep in H+)
Where are the chemoreceptors? Why are they there & what do they sense?
Chemoreceptors = detects changes in CO2, H+, &O2
What happens during quiet inspiration/inhilation?
Inspiration = Air pressure within lungs is lower than atmospheric pressure
Expiration/Exhalation
Expiration = Air pressure within lungs are greater than atmospheric pressure
What causes asthma? How do the symptoms relate to what is happening with the airways?
Asthma =
- Bronchial constriction to the alveoli
What is Pneumonia?
Pneumonia = Acute infection or inflammation of the alveoli (causes fluid to leak into alveoli & will compromise respiration)
What is Bronchitis?
Bronchitis = excessive secretion of bronchial mucous (leading cause is smoking -> cilia are compromised)
What is Emphysema?
Emphysema = destruction of the walls of the alveoli = due to loss of elastic fibers
- smoking, pollution, dust
- creates less surface area for gas exchange
What is SIDS
SIDS = Sudden Infant Death Syndrome = more common in infants of drug abuse, premature babies, etc.
- Stop breathing & doesn’t stop
- Rhythmic generator doesn’t kick in
Where does the respiratory zone start?
What is unique to birds?
- Lungs are stiff & changes little in volume. Has air sacs that can expand and compress
- Have unidirectional flow or air throughout lungs = Highly efficient
- Air sacs = NO GAS EXCHANGE
Bohr Shift? WHy does it matter qualitatively?
- Bohr Shift = The effect of pH on the hemoglobin -> saturation curve caused by CO2
- When pH drops MORE O2 is released -> Curve shift Right (Letting O2 go sooner, Less Affinity)
- When pH rises LESS O2 is released -> Curve shift Left (Letting O2 go later, More Affinity)
What does the P50 determine? How?
P50 = O2 partial pressure @ which the pigment is 50% saturated. Measure affinity = When HB is 50% saturated at a given O2
O2-Hemoglobin Saturation Curve
O2-Hemoglobin Saturation Curve : relationship btwn. partial pressure of O2 in plasma and the percentage of oxygenated respiratory pigment in a volume of blood
Why can’t you sleep @ high altitudes?
What are some adaptations @ high altitudes?
Increased EPO = RBC increase
Increased hematocrit
Peripheral vasodilation
Explain the mechanics of breathing ie volume & pressure changes
What can cause pulmonary edema? Why?
Pulmonary Edema = Fluid accumulation in interstitial spaces and alveoli = could be due to high capillary pressures of increased fluid loss capillaries.
- Due to high BP.
- Can happen @ high altitude.
