The effects of failure of parts of the urinary system may range from inconvenient (incontinence) to fatal (loss of filtration and many others). The kidneys catalyze the final reaction in the synthesis of active vitamin D that in turn helps regulate Ca++. The kidney hormone EPO stimulates erythrocyte development and promotes adequate O2 transport. The kidneys help regulate blood pressure through Na+ and water retention and loss. The kidneys work with the adrenal cortex, lungs, and liver in the renin–angiotensin–aldosterone system to regulate blood pressure. They regulate osmolarity of the blood by regulating both solutes and water. Three electrolytes are more closely regulated than others: Na+, Ca++, and K+. The kidneys share pH regulation with the lungs and plasma buffers, so that proteins can preserve their three-dimensional conformation and thus their function.
osteomalacia
softening of bones due to a lack of mineralization with calcium and phosphate; most often due to lack of vitamin D; in children, osteomalacia is termed rickets; not to be confused with osteoporosis
1. Which step in vitamin D production does the kidney perform?
A) converts cholecalciferol into calcidiol
B) converts calcidiol into calcitriol
C) stores vitamin D
D) none of these
B
2. Which hormone does the kidney produce that stimulates red blood cell production?
A) thrombopoeitin
B) vitamin D
C) EPO
D) renin
C
3. If there were no aquaporin channels in the collecting duct, ________.
A) you would develop systemic edema
B) you would retain excess Na+
C) you would lose vitamins and electrolytes
D) you would suffer severe dehydration
D
1. How does lack of protein in the blood cause edema?
Protein has osmotic properties. If there is not enough protein in the blood, water will be attracted to the interstitial space and the cell cytoplasm resulting in tissue edema.
2. Which three electrolytes are most closely regulated by the kidney?
The three electrolytes are most closely regulated by the kidney are calcium, sodium, and potassium.