Page 1043 - Fundamentals of anatomy physiology

1030 Unit 5 Environmental Exchange

Table 26–6 Typical Values Obtained from Standard Urinalysis

Compound Primary Source Daily Concentration Remarks
Elimination*
1800 mg/dL Increases if negative nitrogen balance
Nitrogenous Wastes exists
150 mg/dL Proportional to muscle mass; decreases
Urea Deamination of amino acids by liver 21 g during atrophy or muscle disease
and kidneys 60 mg/dL

Creatinine Breakdown of creatine phosphate in 1.8 g 40 mg/dL Increases in gout, liver diseases
skeletal muscle 350 g/dL
125 g/dL Gives urine its yellow color
Ammonia Deamination by liver and kidney, 0.68 g 20 g/dL Increase may indicate problem with
absorption from intestinal tract liver elimination or excess production;
causes yellowing of skin and mucous
Uric acid Breakdown of purines 0.53 g membranes in jaundice

Hippuric acid Breakdown of dietary toxins 4.2 mg Primarily glucose; glycosuria develops
if Tm is exceeded
Urobilin Urobilinogens absorbed at colon 1.5 mg Ketonuria may occur during
postabsorptive state
Bilirubin Hemoglobin breakdown product 0.3 mg May increase in some kidney diseases
Note relatively high loss compared with
Nutrients and Metabolites 0.11 g 9 g/dL other metabolites due to low Tm; excess
Carbohydrates (aminoaciduria) indicates Tm problem
0.21 g 17 g/dL
Ketone bodies Varies with diet, urine pH, hormones, etc.
0.02 g 0.002 mg/dL Varies with diet, urine pH, hormones, etc.
Lipids 2.25 g 188 g/dL
Amino acids Hormonally regulated (PTH/CT)

Ions
Sodium 4.0 g 40–220 mEq/L Excess (hematuria) indicates vascular
Potassium 2.0 g 25–100 mEq/L damage in urinary system
Chloride 6.4 g 110–250 mEq/L Excess (pyuria) indicates renal infection or
Calcium 0.2 g 17 mg/dL inflammation
Magnesium 0.15 g 13 mg/dL
Blood Cells‡
RBCs 130,000/day 100/mL

WBCs 650,000/day 500/mL

26 *Representative values for a 70-kg (154-lb) male.
‡Usually estimated by counting the cells in a sample of sediment after urine centrifugation.

Checkpoint 26-6 Urine is transported by the

1 3. What effect would increased amounts of aldosterone ureters, stored in the bladder, and
have on the K concentration in urine? eliminated through the urethra, aided by
the micturition reflex
1 4. What effect would a decrease in the Na concentration
of filtrate have on the pH of tubular fluid? Learning Outcome Describe the structures and functions of the ureters,
urinary bladder, and urethra, discuss the voluntary and involuntary
15. How would the lack of juxtamedullary nephrons affect regulation of urination, and describe the micturition reflex.
the volume and osmotic concentration of urine?
Filtrate modification and urine production end when the fluid
16. Why does a decrease in the amount of Na in the enters the renal pelvis. The urinary tract (the ureters, urinary
distal convoluted tubule lead to an increase in blood
pressure?

See the blue Answers tab at the back of the book.