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Circulatory system: (over-‐simplified)
+ 36-38ATP Depending on the tissue type, Eg. Skeletal muscle vs. cardiac muscle
Transport of O2 and CO2 in the blood
Body Cells
Lungs
Venous blood is slightly acidic @ pH 7.35! Why?
Arterial blood is neutral @ pH 7.4! Why?
(Proton donor) “Weak Acid”
(Proton acceptor)
CO2 (from CR) in the blood combines
with H2O in the blood to form H2CO3
pH of ~ 6.5
(forced rapid breathing-‐ allows for the kid to blow off the CO2)
RegulaHon of Blood pH by the Respiratory System -‐ the bra4y kid in the candy store scenerio
Input
(nerve impulse)
Output
(nerve impulse)
Response
Decreasing pH
HypovenHlaHng
Blood pH (increased levels of H+ in concentraHon)
ppCO2
H+ ; pH < 7.3
detect H+
causes H+
pH > 7.3
enzymes CO2 + H2O ⇔ H2CO3
⇔ H+ + HCO3-
M e t a b o l i c Carbonic acid Bicarbonate Waste
Sample condition #2: Respiratory Alkalosis Hyperventilation - [↓ CO2] ; [↓ H+] ; ↑ pH of blood Respiratory Alkalosis: results from a depressed ppCO2 ( < 35 mm Hg) in arterial blood and a blood pH of > 7.45 i.e. the reaction is driven to the left in this case.
Causes of Respiratory Alkalosis:1) High altitudes2) Pulmonary disease, e.g. Asthma, pneumonia, stroke3) Anxiety4) Hyperventilation due to any of the above causes, or voluntarilyhyperventilating- swimmers were once encouraged to do this in orderto hold their breath longer.
e n z y m e s
CO2 + H2O ⇔ H2CO3 ⇔ H+ + HCO3
-
M e t a b o l i c Carbonic acid Bicarbonate Waste
CO2 in the blood combines with H2O in the blood to form H2CO3
(Delayed breathing-‐ allows for the diver to stay under water longer. > 9 mins. Is the record)
RegulaHon of Blood pH by the Respiratory System -‐ Why a free diver might hypervenHlate before the dive!
Input
(nerve impulse)
Output
(nerve impulse)
Response
Increasing pH
Blood pH (decreased levels of H+ in concentraHon)
Diaphragm contracHons are delayed while CO2 levels climb in the blood
As more H2CO3 forms and more H+ is present, blood pH decreases (H+ concentraHon increases)
HypervenHlaHng ppCO2
H+ ; pH >7.4
detect H+
causes H+
pH < 7.4
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