Physiology: Calculate the total amount of NaCl and volume of urine (= vol of wat
ID: 39501 • Letter: P
Question
Physiology:
Calculate the total amount of NaCl and volume of urine (= vol of water) produced by the average person in each treatment group over the course of the whole experiment after they challenged their renal system with a 1 g salt, 1 L water or both load. Be sure to multiply each osmolarity by its associated volume before calculating the mean. Assume that 40% of the osmolarity of urine is due to NaCl.
Find mmols NaCl produced and g NaCl produced.
I'm just going to give 1 row of data since I have A LOT of data, and I would appreciate it if someone could show me, in detail, how they did this.
Mean Volume Urine Produced: 59.26 mL
Mean Osmolarity: 567.04 mOsm/kg
I know that NaCl has a molecular weight of 49.45 g/mol.
Explanation / Answer
The total rate of glomerular filtration (Glomerular Filtration Rate or GFR) for the whole body (i.e., for all of the nephrons in both kidneys) is normally about 125 ml. per minute. The following calculations may help you visualize how enormous this volume is. The GFR per hour is:
125 ml/min x 60 min/hr = 7500 ml/hr.
The volume of fluid filtered through the glomeruli per day is:
7500 ml/hr x 24 hr/day = 180,000 ml/day or 180 liters/day.