Repiration
CO2 transport
Urinary System
Concurrent Multiplier
Regulation of Kidney
100
What does Dalton’s law say about partial pressures?
Ptotal= P(N2)+P(O2)+P(CO2)+P(other) With elevation change, percentages stay the same but partial pressures change.
100
Name the 3 ways CO2 is transported in the blood. (Which holds the most CO2?)
1) dissolved (10%)
 2) carbamino compounds (30%) 
3) bicarbonate (60%)
100
Name 2 things that the urinary system excretes, and 4 that the urinary system regulates.
Excretes= K+, H+, and Penicillin Regulates= blood pH, blood osmolarity, blood volume, ion concentration, and retains glucose
100
How are the ascending and descending limbs different?
Descending limb: poorly invaginated, few mitochondria. permeable to water, Impermeable to Na+. As filtrate travels down limb the volume is reduced and osmolality increased. Max osmolality is 1200mOsm. Ascending limb: impermeable to water but permeable to solutes. Thick ascending limb full of mitochondria. In the think ascending limb, NaCl moves passively down a concentration gradient through transporters into the ECF. Impermeable to water but permeable to NaCl. As filtrate moves toward thick ascending limb osmolality drops approaching 400mOsm by the end of the thin ascending limb.
100
Describe tubuloglomerular feedback.
Mechanism that regulates GFR. High NaCl concentration means elevated GFR while low NaCl concentration indicates a low GFR. NaCl sensed by macula densa. Local Regulation: paracrine and myogenic response Hormone regulation: secretion of Renin which starts the aldosterone cascade.
200
How does partial pressure of O2 change as air moves into the lungs.
The partial pressure of O2 from the air into lungs is 159mmHg but moisture in lungs reduces the partial pressure to 105mmHg
200
What is the chloride shift?
When bicarbonate is made, the bicarb ion diffuses out of the cell, but H+ remains in the cell, so Cl- diffuses in to maintain electrical neutrality
200
Name 4 organs in the urinary system in order, starting with where urine is first produced/processed.
kidneys, ureters, bladder, urethra
200
What is meant by hyperosmotic and hyposmotic when talking about the fluid in the loop of Henle? How does the filtrate volume change as it flows through the loop of Henle?
Hyperosmotic will have more concentration of salts/solutes and hypo osmotic has relatively little solutes. Moving down descending limb volume is reduced, moving up ascending limb
200
Where is aldosterone secreted and what triggers this secretion? What ion is reabsorbed in response to increased levels of aldosterone?
- Secreted in blood. - Release of Renin because of decrease in blood pressure and GFR. - Na+ and H2O are retained in the Kidneys.
300
What is the relationship between O2 partial pressures in the lungs (alveoli) and blood.
The partial pressure of O2 from alveoli is 105 and in arterial blood it is 100. At venous ends the partial pressures are equal.
300
How are blood CO2 levels and blood pH related? (know the bicarbonate reaction by heart)
CO2 + H2O <-—> H2CO3 <--> H+ + HCO3- When blood CO2 levels increase the pH decreases because CO2 combines with H20 to produce carbonic acid (H2CO3) which dissociates and liberate an H+ ion.
300
Name all the tubules of the kidney through which filtrate/urine must pass, starting with the glomerular capsule and ending with the renal pelvis.
proximal convoluted tubule, loop of Henle, distal convoluted tubule
300
What is the countercurrent multiplier system?
a mechanism that expends energy to create a concentration gradient within the loop of Henle. Countercurrent because filtrate moves in opposite directions in descending and ascending limbs of the Loop of Henle. Multiplication because countercurrent flows enables effects of gradient to be increased (multiplied). Enables interstitial fluid to be more concentrated which allows water to be passively moved out resulting in more concentrated urine.
300
Potassium and hydrogen ion secretion take place in the distal convoluted tubule. What stimulates H ion secretion?
On the filtrate side, intercalated cells have a K+-H+ ATPase that moves K+ into the cell and H+ out of cell into the filtrate. Another active process is the H+ ATPase which moves H+ into the filtrate. Both mechanisms use carbonic acid from water and CO2 to eliminate H+ and create new bicarbonate buffering ions for the blood.
400
What does Henry’s law tell you about how O2 travels in the blood?
It travels in RBC through hemoglobin
400
What is the most direct stimulus that causes us to take a breath?
Increase in CO2
400
What are the names of the blood vessels going in/out of the glomerulus?
afferent arteriole goes to glomerulus and efferent arteriole goes away from glomerulus
400
What is another word for vasopressin?
ADH
400
What role does carbonic anhydrase (CA) play in bicarbonate ion reabsorption? Does any step in this process require ATP? Why might the body increase bicarbonate reabsorption?
Carbonic Anhydrase is an enzyme that converts H2CO3 into H2O and CO2 OR CO2 and H2O into H2CO3. An increase in HCO3, luminal flow rate, arterial partial pressure of CO2, or angiotensin II will cause in increase in bicarbonate reabsorption.
500
What is the relationship between O2 partial pressure in the blood plasma and O2 content in whole blood (remember hemoglobin).
Only small amount of O2 is dissolved in plasma. Much larger amount of oxygen is bound to hemoglobin contained within RBC’s of arterial blood.
500
What is the effect of hypoventilation and hyperventilation on 1) CO2 levels in the blood, 2) pH of the blood, 3) O2 levels in the blood?
Hypoventilation (decreased breathing) increases CO2 levels in the blood, decreases O2, pH decreases Hyperventilation (increased breathing) decreases CO2 levels in the blood, O2 may change some but you can only have so many oxygen, pH increases
500
What is the smallest functional unit of the kidney?
Nephron
500
What is the zone of auto-regulation?
Range of blood pressures, regulated via tubuloglomerular feedback
500
How is the hypothalamus involved in the body’s response to dehydration? What does the sympathetic nervous system do in response to a decrease in blood pressure and/or volume?
Osmolality sensed by osmoreceptors in hypothalamus which signals Post. Pit. to secrete ADH which increases retention of water in Kidneys. A decrease in blood pressure or volume would signal the adrenal cortex to release aldosterone so Na+ and H2O are retained and the blood volume goes up.
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