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RENAL PHYSIOLOGY TUTORIAL-2 DISCUSSION

Dr. Zahoor

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TOPICS

• Counter Current Mechanism• Acid Base Balance

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Q1. What does word ‘Counter Current’ means?

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Q2. Name the four mechanisms which help in counter current mechanism (concentration mechanism of urine).

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Q3. How loop of Henle (counter current multiplier) establishes the concentration gradient in the renal medulla?

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Q4. What is the role of Vasarecta (counter current exchanger) in the counter current mechanism?

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Q5. Why medullary interstial Osmolarity is important for concentration of urine?

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Q6. If there is no medullary concentration, what will happen?

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Q7. What is the Osmolarity of interstial fluid in the medullary interstium?

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Q8. What is the role of ADH in the concentration mechanism of urine?

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Q9. Where does the ADH act on DCT and CT?

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Q10. How much water is reabsorbed in the DCT and CT under the action of ADH?

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Q11. If ADH is not there, urine will be concentrated or dilute?

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Q12. If a person is fasting and has taken no water for 10 hours, why he passes less amount of concentrated urine?

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Q13. If a person drinks 1 liter of water, why he passes more amount of dilute urine?

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Q14. What is role of urea in the concentration mechanism of urine?

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Q15. What is urea cycle in the counter current mechanism?

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Q16. What is Micturition or urination reflex?

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Q17. Where is the center for Micturition reflex?

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Q18. Urinary bladder smooth muscle contraction is function of (select one)1. Sympathetic ANS2. Parasympathetic ANS

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Q19. What is the capacity of normal urinary bladder in the adult person?

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Q20. As urine is collected in the urinary bladder, when initial urge is felt for urination?

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Q21. Urination is under voluntary control, how?

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Q22. What is pH?

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Q23. What is pH of water?

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Q24. What is pH of blood?

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Q25. In the human, what pH is compatible with life?

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Q26. If pH or arterial blood is 7.3, is it normal or abnormal?

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Q27. If H+ ion increases, pH will be:

Select one1. Acidic2. Alkaline

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Q28. What is normal pH of urine?

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Q29. What could be the lowest pH of urine?

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Q30. Why pH of blood, if acidic or alkaline is dangerous for the body?

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Q31. How body regulates the pH. Give three defense mechanism.

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Q32. What are body chemical buffers which operate in seconds?

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Q33. How respiration regulates the acid base balance?

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Q34. What is the role of kidney in acid base balance?

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Q35. How kidney secretes H+ ion? Draw diagram.

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Q36. Where H+ ion is secreted in the tubule?

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Q37. How new HCO3- ion is generated and

reabsorbed?

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Q38. Name the kidney buffers?

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Q39. If there is metabolic alkalosis, what does the kidney do?

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Q40. In Respiratory acidosis/alkalosis, what will happen to

Resp. acidosis Resp. alkalosis

pH

CO2

HCO3

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Q41. In metabolic acidosis/alkalosis, what will happen to Meta. acidosis Meta. alkalosis

pH

CO2

HCO3

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Q42. If a person has vomiting, his blood pH is found to be 7.5CO2 38mmHg, HCO3 34meq/l.What type of acid base disorder he is having?

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THANK YOU