2.  HOW THE KIDNEY REGULATES BLOOD Ph  IF THE BLOOD IS ACIDIC (LOW pH)  KIDNEY BRINGS IT BACK TO NORMAL BY EXCRETING HYDROGEN IONS AND AMMONIA  KIDNEY REABSORBS SODIUM IONS AND BICARBONATE

3.  IF THE BLOOD IS ALKALINE (HIGH pH)  FEWER HYDROGEN IONS ARE EXCRETED AND FEWER SODIUM AND BICARBONATE IONS ARE REABSORBED

4.  JUXTAGLOMERULAR CELLS SECRETE RENIN  RENIN INITIATES THE RENIN-ANGIOTENSIN MECHANISM WHICH RAISES BLOOD PRESSURE

5.  ERYTHROPOIETIN  STIMULATES THE RED BONE MARROW TO INCREASE PRODUCTION OF RED BLOOD CELLS

6.  ANTIDIURETIC HORMONE (ADH)  HELPS MAINTAIN BLOOD VOLUME AND BLOOD PRESSURE BY INCREASING REABSORPTION OF H2O  PARATHYROID HORMONE (PTH)  INCREASES REABSORPTION OF Ca FROM FILTRATE TO THE BLOOD AND EXCRETION OF PHOSPHATE INTO THE FILTRATE

7.  ALDOSTERONE  HELPS MAINTAIN BLOOD VOLUME AND BLOOD PRESSURE BY STIMULATING REABSORPTION OF Na+ IONS AND EXCRETION OF K+  ATRIAL NATRIURETIC HORMONE (ANH)  DECREASES REABSORPTION OF Na+ IONS; INCREASES Na+ AND H20 EXCRETED

8. Disease/DisorderDescription Acute renal failureSudden loss of kidney function; may be reversible with treatment Chronic renal failureKidneys slowly lose ability to function; not reversible CystitisUrinary bladder infection; more common in females GlomerulonephritisInflammation of the glomeruli of the kidney; one cause of chronic renal failure IncontinenceInability to control urination

9. Disease/DisorderDescription Polycystic kidney disease Enlargement of kidneys because of the presence of many cysts within them; slow, progressive disease PyelonephritisComplicated urinary tract infection; starts with a bladder infection and spreads to both kidneys; can be acute or chronic Renal calculiKidney stones; can become lodged in ducts within kidneys or ureters