TLS Online TPP Program

#Question id: 5663


Following statements are related to slow block to polyspermy in mammals.

A. A First slow block to polyspermy comes When the cortical granules fuse with the egg cell membrane, they release protein-digesting enzymes which is called as ovastacin that modify the zona pellucida proteins.

B. A second slow block to polyspermy comes from the so-called zinc spark, the release of billions of zinc ions that is induced by the entry of the first sperm, these released zinc ions are seen to bind to the egg cell membrane form a “zinc shield” that prevents further sperm entry.

C. A third slow block to polyspermy occurs at the level of the egg cell membrane and involves Juno.

Which of the following is incorrect?

#Unit 5. Developmental Biology
  1. A, B and C

  2. B only

  3. A and B

  4. A and C

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TLS Online TPP Program

#Question id: 12698

#Unit 7. System Physiology – Animal

The following test results were obtained: urine flow rate = 2.0 ml/min; urine inulin concentration = 60 mg/ml; plasma inulin concentration = 2 mg/ml; urine potassium concentration = 20 μmol/ml; plasma potassium concentration = 4.0 μmol/ml; urine osmolarity = 150 mOsm/L; and plasma osmolarity = 300 mOsm/L. What is the net potassium reabsorption rate?

TLS Online TPP Program

#Question id: 12697

#Unit 7. System Physiology – Animal

The following test results were obtained: urine flow rate = 2.0 ml/min; urine inulin concentration = 60 mg/ml; plasma inulin concentration = 2 mg/ml; urine potassium concentration = 20 μmol/ml; plasma potassium concentration = 4.0 μmol/ml; urine osmolarity = 150 mOsm/L; and plasma osmolarity = 300 mOsm/L. What is the approximate GFR?

TLS Online TPP Program

#Question id: 12659

#Unit 7. System Physiology – Animal

 Which of the following would tend to decrease plasma potassium concentration by causing a shift of potassium from the extracellular fluid into the cells?

TLS Online TPP Program

#Question id: 12658

#Unit 7. System Physiology – Animal

In a person on a high (200 mmol/day) potassium diet, which part of the nephron would be expected to secrete the most potassium?

TLS Online TPP Program

#Question id: 12561

#Unit 7. System Physiology – Animal

Given the following measurements, calculate the filtration fraction: glomerular capillary hydrostatic pressure = 50 mm Hg; Bowman’s space hydrostatic pressure = 15 mm Hg; colloid osmotic
pressure in the glomerular capillaries = 30 mm Hg; glomerular capillary filtration coefficient (Kf) = 12 ml/min/mm Hg; and renal plasma flow = 400 ml/min.

TLS Online TPP Program

#Question id: 12560

#Unit 7. System Physiology – Animal

If GFR suddenly decreases from 150 ml/min to 75 ml/min and tubular fluid reabsorption simultaneously decreases from 149 ml/min to 75 ml/min, which of the following changes will occur (assuming that the changes in GFR and tubular fluid reabsorption are maintained)?