Kidney, Body Fluids, and Acid-Base Balance

Most important buffer in interstitial fluid:

A. Phosphate

B. Bicarbonate

C. Histidine

D. Protein

Renin is secreted by:

A. cortical interstitial cells

B. cells in macula densa

C. granular cells

D. mesangial cells

Least clearance is for among these

A. Glucose

B. Inulin

C. Urea

D. Creatinine

PCT absorbs all except:

A. Sodium

B. Glucose

C. Hydrogen ions

D. Amino acids

Concentrating ability of kidney is impaired if:

A. there is damage to the glomerulus

B. there is excess secretion of ADH

C. there is vigorous activity of Na+-K+-pump

D. blood flow through the vasa recta is increased substantially

Ideal substance for measuring GFR should have all characteristics except

A. Should be secreted in tubules

B. Should be nontoxic

C. Should not remain in the body

D. Should not be protein bound

The prime driving force for countercurrent multiplier system is:

A. Medullary hyperosmolarity

B. Reabsorption of Na+ in thick ascending limb

C. Action of ADH via aquaporin channels

D. Urea recycling

The renal plasma flow (RPF) of a patient was to be estimated through the measurement of Para Amino Hippuric acid (PAH) clearance. The technician observed the procedures correctly but due to an error in the weighing inadvertently used thrice the recommended dose of PAH. The RPF estimated is likely to be

A. False-high

B. False-low

C. False-high or false-low depending on the GFR

D. Correct and is unaffected by the PAH overdose

Normal anion gap metabolic acidosis is seen in:

A.Diarrhoea

B.Renal failure

C. Lactic acidosis

D.Diabetic ketoacidosis

A substance is present in concentration of 2 mg% in the afferent arteriole and zero mg% in the efferent. True about the substance is:

A. It is freely filtered at the glomerulus

B. Secreted in cortical nephron

C. Absorbed in PCT

D. Impermeable in loop of Henle

If a substance X has more renal clearance than the GFR, it means:

A. X is only being reabsorbed by the tubules

B. X is being secreted by the tubules

C. X is being secreted as well as reabsorbed by the tubules

D. X is neither secreted nor reabsorbed

General Physiology, Nerve & Muscle The distribution of diffusible ions between two compartments separated by a semipermeable membrane in the presence of non-diffusible ions in one of the compartments, is given by: A. Nernst equation

B. Handerson Hasselbach equation

C. Gibbs-Donnan equation

D. Hodgekin-Huxley-Katz equation

In an adult man weighing 70 kg, the extracellular fluid volume will be about:

A.42 L

B.28 L

C.14 L

D.12 L

Glucose transport into the gut cells is an example of:

A. simple diffusion

B. facilitated diffusion

C. symport

D. antiport

The Extracellular fluid that has high potassium and low sodium levels is:

A. Synovial fluid

B. Endolymph

C. Ectolymph

D. CSF

Nernst potential of Sodium is:

A. 89 mV

B. 96 mV

C. + 61 mV

D. + 45 mV

All of the following are examples of primary active transport, except

A. The Na+/K+ ATPase in the red cell membrane

B. The H+/K+ ATPase in the parietal cell of stomach

C. Na+/glucose symporter

D. SERCA in the skeletal muscle

Facilitated diffusion is characterized by all except:

A. Vmax

B. Competitive inhibition

C. Requires energy

D. Specificity

Which of the following nerve fibers are unmyelinated?

A. Type Ia

B. Type II

C. Type III

D. Type IV

Myelin in CNS is formed by:

A. Oligodendrocytes

B. Schwann cells

C. Microglia

D. Astrocytes

Chronaxie is:

A. Stimulation of the fiber by least possible voltage

B. The time required for this least voltage to excite the fiber

C. Time required to excite a fiber when stimulus is twice the rheobase strength

D. An electrical current artificially induced through a nerve causes excess flow of ions through the axonal membrane

True about end plate potential is:

A. It occurs as a result of altered permeability for Na+ and K+

B. It is a self-regenerative change

C. It results from release of a single transmitter vesicle

D. It exhibits all-or-none property

Tetanizing stimulation of the muscle causes a sustained forceful contraction due to:

A. Recruitment phenomenon

B. Failure of Ca++ removal from the sarcoplasm

C. Summation of the stimuli

D. Beneficial effect

Pale fiber type of skeletal muscle is:

A. Fast contracting, susceptible to fatigue

B. Slow contracting, susceptible to fatigue

C. Fast contracting, resistant to fatigue

D. Slow contracting, resistant to fatigue

In malignant hyperthermia, excess heat production is due to:

A. Increased muscle metabolism by excess of calcium ions

B. Thermic effect of food

C. Increased sympathetic discharge

D. Mitochondrial thermogenesis

A travelling nerve impulse does not depolarize the area immediately behind it, because:

A. It is hyperpolarised

B. It is refractory

C. It is not self-propagating

D. The conduction is always orthodromic

Initiation of nerve impulse occurs at the axon hillock because:

A. It has a lower threshold than the rest of the axon

B. It is unmyelinated

C. Neurotransmitter release occurs here

D. None of the above