ILA 2 - Salt And Water SBA Flashcards
Aldosterone promotes sodium reabsorption in the kidneys.
Where is aldosterone synthesised?
A. Adrenal cortex
B. Anterior pituitary
C.Distal tubules and collecting ducts of nephron
D. Hypothalamus
E. Juxtaglomerular cells
F. Posterior pituitary
A. Adrenal cortex
Aldosterone:
Steroid hormone released from the adrenal cortex in response to stimulation by angiotensin II.
It promotes sodium reabsorption and potassium secretion in the distal tubules of the kidneys.
Anti-diuretic hormone (ADH) acts on the kidneys to promote water retention.
What is the site of synthesis of ADH (antidiuretic hormone)?
A. Adrenal cortex
B. Anterior pituitary
C.Distal tubules and collecting ducts of nephron
D. Hypothalamus
E. Juxtaglomerular cells
F. Posterior pituitary
D. Hypothalamus
ADH:
Synthesised by the supraoptic and paraventricular nuclei of the hypothalamus.
However it is then stored in the posterior pituitary gland.
A GP suspects that his young patient has cranial diabetes insipidus. This is a disorder in which the pituitary gland fails to release ADH when stimulated to do so. She is referred for a water deprivation test during which she is nil by mouth.
If the patient does have diabetes insipidus and is not producing any ADH which of the following is MOST LIKELY to show her blood and urine osmolality after 3 hours of water deprivation?
A. Blood 220/urine 100
B. Blood 220/urine 1200
C. Blood 300/urine 100
D. Blood 300/urine 1200
E. She won’t produce urine
C. Blood 300/urine 100
During the water deprivation test the body should detect an increased serum osmolality (300) and produce ADH in order to promote water retention.
As she is unable to produce ADH she will produce dilute urine (low osmolality, 100) instead of concentrated urine.
A diagrammatic representation of the relative amounts of intracellular cations (1st column) and anions (2nd column) is shown. Which of the following are MOST LIKELY represented by the letters Y and Z?
PHOTO ON ILA FORMATIVE
A. K and HCO3
B. K and lactate
C. Na and HCO3
D. Na and K
E. Na and lactate
A. K and HCO3
Y. Potassium is most prevalent cation within the cell.
Z. Bicarbonate is the missing anion.
Renin is a proteolytic enzyme
Which of the following describes the action of renin?
A. Angiotensin 1 to angiotensin 2
B. Angiotensin 2 to angiotensin 1
C. Angiotensinogen to angiotensin 1
D. Angiotensinogen to angiotensin 2
C. Angiotensinogen to angiotensin 1
Renin is a proteolytic enzyme which activates angiotensinogen to produce angiotensin I.
You examine a patient and note they have pitting oedema of their ankles. Blood tests show that their blood albumin level is low.
Which statement correctly describes the relationship between albumin and oedema?
A. A low albumin causes a decrease in oncotic pressure and water diffuses from the interstitial fluid into the blood
B. A low albumin causes a decrease in oncotic pressure and water diffuses from the blood into the interstitial fluid
C. A low albumin causes an increase in oncotic pressure and water diffuses out of the blood into interstitial fluid
D. A low albumin causes an increase in oncotic pressure and water diffuses from the interstitial fluid into the blood
E. Low albumin is not related to oedema
B. A low albumin causes a decrease in oncotic pressure and water diffuses from the blood into the interstitial fluid
A low albumin causes a decrease in oncotic pressure and water diffuses from the blood into the interstitial fluid
A healthy student drinks 2 litres of water in 5 mins. Which of the following correctly describes the physiological response?
A. Osmolality falls >ADH secretion increase> increased urine volume
B. Osmolality falls >ADH secretion stops > increased urine volume
C. Osmolality rises >ADH secretion increase >increased urine volume
D. Osmolality rises >ADH secretion stops >increased urine volume
B. Osmolality falls >ADH secretion stops > increased urine volume
The excess fluid causes a decrease in blood osmolality (osmolarity) which in turn causes a reduction / stopping of Anti Diuretic Hormone release. The kidneys therefore excrete more water leading to increased urine volume.
During an illness patients can lose fluid in a variety of ways.
Which of the following is an example of insensible fluid loss?
A. Diarrhoea
B. Fluid in an abdominal surgical drain
C. Urine
D. Vomiting
E. Water from respiration
E. Water from respiration
Insensible fluid loss is loss that is not easily measured e.g. sweating, water lost from respiration, evaporation during abdominal surgery.
Sensible fluid loss is that which is easily measured e.g. urine output, vomit, fluid in surgical drains.
Renin is a proteolytic enzyme.
What is the principal site of renin production?
A. Adrenal cortex
B. Anterior pituitary
C.Distal tubules and collecting ducts of nephron
D. Hypothalamus
E. Juxtaglomerular cells
F. Posterior pituitary
E. Juxtaglomerular cells
Osmolarity can be calculated from a patient’s blood results.
Which of the following is a factor in calculated osmolarity?
A. Bicarbonate
B. Chloride
C. Magnesium
D. Phosphate
E. Urea
E. Urea
2 x na+ + glucose (mg/dl)/18 +BUN(mg/dl)/2.8
Total body water (TBW) is distributed into three compartments (Intracellular/interstitial/intravascular).
How is the TBW distributed by volume? (Assume healthy 70 Kg man)
A. 42L/11L/3L
B. 28L/14L/3L
C. 28L/11L/3L
D. 24L/14L/3L
E. 24L/11L/3L
C. 28L/11L/3L
Intracellular 28L. Interstitial 11L. Intravascular 3L.
