Wednesday, March 14, 2018

Renal system-Physiology MCQs

1. Vasa recta is formed by
A) The cortical nephron’s peritubular capillaries
B) The juxta medullary nephron’s peritubular capillaries
C) The distal tubule
D) The proximal tubule
Ans: B
2. How many % of nephrons in humans are cortical nephrons?
A) 20%
B) 30%
C) 50%
D) 80%
Ans: 80%
3. Counter current mechanism takes place in
A) Cortical nephrons
B) Renal pelvis
C) Juxta medulary nephrons
D) None of the above
Ans: C
4. Which of the following parts of tubular segment is always impermeable to water?
A) Descending limb of loop of henle
B) Ascending limb of loop of henle
C) Collecting duct
D) Proximal convoluted tubule
Ans: B
5. Which of the following substances is actively reabsorbed in the proximal tubule and actively secreted in the distal & collecting tubule?
A) Na+
B) H+
D) Glucose
Ans: C
6. If ascending limb of loop of Henle is permeable to water, what would be the minimum/maximum urine Osmolarity the person could produce?
A) 300/1200
B) 1200/1200
C) 300/300
D) 100/100
Ans: C
7. Bowman’s capsule colloidal osmotic pressure is
A) 32
B) 60
C) 18
D) 0
Ans: D
8. The normal glomerular capillary colloid osmotic pressure is
A) 32
B) 60
C) 18
D) 0
Ans: A
9. Glomerular capillary pressure is
A) 32
B) 60
C) 18
D) 0
Ans: B
Explanation: Compared with other capillaries [17 mmHg], the glomerular pressure is very high [60 mmHg] and favours filtration.
10. Renal vascular resistance resides mainly in
A) Renal A & Glomerular capillaries
B) Interlobar, Afferent & Efferent arterioles
C) Glomerular capillaries & Renal vein
D) Renal A & Arcuate Vein
Ans: B
Explanation: Increase in resistance decreases RBF, whereas ↓ in resistance ↑ RBF.
11. Which of the following substances causes ↑ GFR?
A) Epinephrine
B) AngiotensinII
C) Prostaglandins
D) Norepinephrine
Ans: C
12. The flat segment in the graph of the cystometrogram is a manifestation of
A)  Fick’s law
B) Boyel’s law
C) Law of Laplace
D) Ohm’s law
Ans: C
13. In the presence of ADH, the greatest fraction of filtered water is absorbed in the
A) Cortical collecting duct
B) Distal tubule
C)Henle’s loop
D) Proximal tubule
Ans: D
14. The major site of renal gluconeogenesis is
A) Proximal tubule
B) Loop of Henle
C) Distal tubule
D) Collecting tubule
Ans: A
Explanation: Renal gluconeogenesis occurs only in unusual circumstances like prolonged starvation& chronic respiratory acidosis.
15. Renal O2 consumption is approximately
A) 6ml/100 g tissue/mt
B) 20ml/100 g tissue/mt
C) 25ml/100 g tissue/mt
D) 30ml/100 g tissue/mt
Ans: A
16. Darrow-Yannet diagram
A) Represents counter-current mechanism
B) Represents cystometrogram
C) Simplify the clinical analysis of fluid balance
D) Represents auto regulation of blood flow
Ans: C
17. Afferent arteriole constriction
A) ↓ both RPF&GFR
B) ↑ both RPF&GFR
Ans: A
18. Afferent arteriole dilatation
A) ↓ both RPF&GFR
B) ↑ both RPF&GFR
Ans: B
19. Constriction of Efferent arteriole
A) ↓ both RPF&GFR
B) ↑ both RPF&GFR
Ans: C
20. Dilatation of Efferent arteriole
A) ↓ both RPF&GFR
B) ↑ both RPF&GFR
Ans: D
21. Juxta glomerular cells are
A) Baroreceptors
B) Chemoreceptors
D) Light receptors
Ans: A
22. Macula densa cells are
A) Baroreceptors
B) Chemoreceptors
C) Telereceptors
D) Light receptors
Ans: B
23. Fluid in the early distal tubular segment is
A) Iso tonic
B) Hypo osmotic
C) Hyper osmotic
D) Regardless of whether ADH is present or not
Ans: B
24. Obligatory urine volume is
A) 0.5 L/day
B) 1L/day
C) 1.5L/day
D) 50 ml/day
Ans: A
25. The active pump in the thick ascending limb on the loop of Henle establishes the following concentration gradient between tubular fluid and interstitial fluid.
A) 500 mOsm/L
B) 400 mOsm/L
C) 300 mOsm/L
D) 200 mOsm/L
Ans: D
26. Urea transporter UT-A1 is activated by
B) AngiotensinII
C) ↑ blood volume
D) ↑ blood pressure
Ans: A
27. Plasma Osmolarity can be approximately calculated as
A) 2.1 ×plasma Na+ conc.
B) 2.1 ×plasma K+ conc.
C) 2.1 ×plasma Cl conc.
D) 2.1 ×plasma Hco3 conc.
Ans: A
28. The most important Extracellular buffer is
A) Protein
B) Hco3
C) Phosphate
D) Ammonia
Ans: B
29. Total acid production in the body is derived from
A) Oxidative metabolism
B) Protein catabolism
C) Triglyceride catabolism
D) Lipoprotein metabolism
Ans: A
Explanation: The greatest source of H+ is the CO2 produced during oxidative metabolism. About 13,000 mmol of Co2 daily or 13,000 mEq of H /day
30. The major fraction of 80% of the total Co2 in the bone is in the form of
A) Carbonic acid
B) Bicarbonate
C) Carbonate
D) Hb
Ans: C
Explanation: about 2/3 rds of total Co2 is in the form of carbonates combined with Na, Ca & other cations in bone crystals. The remaining 1/3 rd consists of Hco3.The total bone carbonate is 50 times the amount of Hco3 found in the ICF & ECF together.
31. H+ secretion in the proximal tubule occurs primarily by
A) Primary active transport
B) Secondary active transport
C) Facilitated diffusion
D) Simple diffusion
Ans: B
32. H+ secretion in the late distal tubule occurs by
A) Primary active transport
B) Secondary active transport
C) Facilitated diffusion
D) Simple diffusion
Ans: A
33. Which of the following would be expected to cause ↑H secretion & Hco3 Reabsorption?
A) ↓ AngiotensinII
B) ↑ ECF volume
C) ↓ Aldosterone
D) ↑ Pco2
Ans: D
34. In the renal regulation of acid base balance, new Hco3 is formed by
A) Hco3 buffer system
B) Phosphate buffer system
C) Ammonia buffer system
D) B& C
Ans: D
35.In ECF the total concentration of cations exceeds that of anions.
Ans: false-these must be equal.Anion gap is not true deficit.
36.The acid buffering power of venous blood is greater than arterial blood.
 Ans: True.Hco3 is slightly higher in venous blood. deoxy Hb is a betterbuffer.
38.In arterial blood metabolic alkalosis may be caused by tissue anoxia.
Ans:false.may cause metabolic acidosis through anaerobic metabolism
39.Micturition is a sacral spinal reflex.
40.If systemic blood pressure falls by 50% GFR drops to 0.
Ans:true.sympathetically driven constriction of efferent arteriole.

Friday, July 7, 2017

My parents sadhabishegam

Role model in my life
Role model in our life need not necessarily be a celebrity.Many times in life ,we come across a strong ,influential person who leaves a great and powerful impact on our role models are my parents.They are my pillars of strength.I thank God for celebrating this beautiful occasion.

Sunday, December 27, 2015


I wish you achieve all your goals in life,and get success at every step of life.

                                HAPPY NEW YEAR 2016

Sunday, July 12, 2015


Hi all,
         Published a book entitled:APPLIED PHYSIOLOGY SECRETS

Ø    This book has been designed for medical students to think critically and intellectually to enhance their knowledge.
Ø   Questions in the form of short notes, reasoning out, comments and controversies.
Ø  Ideal for self assessment, M.D physiology postgraduates, PG basic science and M.B.B.S  examination.

Ø   Covers even difficult concepts in physiology. Some questions also include clinical perspective concepts.


 Dr.R.Vinodha is professor&HOD of physiology at Thanjavur medical college,Thanjavur.She graduated M.B.B.S from thanjavur medical college in 1987 and completed M.D(physiology) in 1993 at Madras medical college,Chennai.She has been teaching physiology for the last about 20 years.
  She has published papers in national and international journals. She guides and encourages students through e-learning by publishing many articles and MCQs in She was a senate member of T.N Dr.M.G.R Medical University from 2011-2014.

Educreation publishing:available online-e-book and print

Sunday, July 5, 2015

control of speech


If only people did remain a little quiet before speaking, acting or writing, much trouble could be avoided. So many things are said uselessly, they bring misunderstandings and bad feelings which could have been saved with silence. If were spoken only the words that needed to be spoken the world would be a very silent place.

Thursday, December 18, 2014

Green is better than red

                             Green is better than red

An apple a day:
Can it really keep the doctor away?
  People who eat apples frequently are less likely to have heart attacks or stroke or to develop several kinds of cancer. Apples are naturally packed with a variety of nutrients such as proteins,vitamins(C,A,E,Riboflavin),minerals(iron,Ca,Mg,K,),antioxidants (flavonoid&polyphenol).Apples are known for its excellent source of pectin, a soluble fiber found beneath the skin is responsible for the regulation of cholesterol.
There are varieties of apple, yellow, green and the most popular one is the red.
Did you know that green apples are far better in terms of health benefits?
Green apples provide many health as well as cosmetic benefits like improvement of skin texture and hair growth. It contains a lot of fiber, which helps in the regulation of bowel movements. It stabilizes blood sugar and cholesterol. Green apples contain less amount of fructose than red, which can be consumed by diabetic patients. (Glycemic index for apple is 38).The best way is to consume it as a whole fruit usually eaten raw, so that it retains all the nutrients. But they are also used in various recipes.
Here are some different south Indian style recipes:
Apple pachadi-
Apple-3(cut into small pieces without skin)
Jaggery syrup -2 tbsp
Turmeric powder-1/4 tsp
Red chilli powder-1/4 tsp
Cardamom powder-1/4 tsp
Ghee/Oil- 1tsp
Salt-as required
To season: mustard seeds, Black gram dhal, Red chilli-1

Method: Heat a teaspoon of oil in a pan season with mustard seeds, black gram dhal&red chilli. Add apple pieces, turmeric powder, chilli powder and salt.Stir gently for few seconds. Add ¼ cup of water and cook for 2 mts.when apples become tender add jiggery syrup .Before removing from fire add cardamom powder. Serve with rice or poori.
Note: 1.To removes impurities in jiggery –jaggery syrup is used. (Add 1 cup jiggery and ¾ cup water. Melt and boil for 2 mts.Then strain to remove impurities. This can be stored.)
2. Cardomom powder is optional.
Apple sambar
Red gram dhal-(tuvar-toor-thuvaram parupu)-1/2 cup
Green apple cut into big pieces-3 tbsp
Small onions-1 tpsp
Green chilli-1 sliced
Turmeric powder-1tsp
Red chillipowder-1/2 tsp
Coriander powder-1tsp
Sambar powder-1tsp
2 pinches of asafoetida, salt, curry leaves, coriander leaves.

Wash the dhal and add 11/2 cups of water in a pressure cooker &cook for 4 whistles. Heat a teaspoon of oil in a pan; add mustard seeds, black gram dhal, curry leaves&asafoetida sauté on a medium flame for a few seconds. Add onions, green chillies, fry for 2 mts.Add tomatoes, turmeric powder, coriander powder, and chilli powder mix well and cook for 1 mt.then add apple, stir &cook for another 1 mt, and add the cooked dal, salt, sambar powder, coriander leaves .Mix well and cook on a medium flame for 2 mts.sambar can be served with steamed rice, dosas, idlis and appams.

Saturday, March 8, 2014

CME on ECG basics &in clinical practice

Department of physiology
Thanjavur medical college,
             CME on ECG basics & in clinical practice
             on 26th march 2014-8.30am to 1.45 pm
              venue: new exam hall,TMC(you can learn the hidden secrets about ECG &CME credit points will be awarded)