A patient lost a lot of blood during surgery and his blood pressure dropped from 120/80 to 90/50. Describe how the kidneys respond to this change in blood pressure.

What will be an ideal response?


When arterial blood pressure declines, special cells in the kidneys release the enzyme renin into the blood. Renin triggers a series of enzymatic reactions that produce angiotensin II, which is a potent vasoconstrictor. Angiotensin causes an increase in systemic blood pressure, and increases the rate of blood delivery to the kidneys and renal perfusion. It also stimulates the adrenal cortex to secrete aldosterone, a hormone that enhances renal reabsorption of sodium, and prods the posterior pituitary to release ADH, which promotes more water reabsorption. As sodium moves into the bloodstream, water follows; thus both blood volume and blood pressure rise.

Anatomy & Physiology

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Which of the following is a not a true statement regarding the countercurrent multiplication system?

A) The thin limb of the nephron loop is permeable to water. B) The thick limb of the nephron loop is permeable to solutes. C) Osmotic concentration in the nephron loop decreases as fluid flows toward the bottom of the loop. D) Tubule fluid arrives at the DCT at about 100 mOsm/L. E) The maximum solute concentration is about 1200 mOsm/L.

Anatomy & Physiology

Which of the following membranes line cavities that communicate with the exterior of the body?

A) mucous B) serous C) cutaneous D) synovial E) pleural

Anatomy & Physiology

Of the two types of synapses, based on mode of communication, which is less common but allows faster signal transmission?

A.   Chemical synapse B.   Mechanical synapse C.   Physical synapse D.   Magnetic synapse E.   Electrical synapse

Anatomy & Physiology

The belly button is located in which region?

A. Epigastric B. Umbilical C. Iliac D. Hypogastric

Anatomy & Physiology