Explain the following observations in human; production of large volumes of dilute urine on cold day; urine production almost stops as a result of serious blood loss; presence of sugar in urine; feeling hungry faster in cold weather

• Production of large volumes of dilute urine on cold day

On cold day little or no sweating occurs, loss of water through the skin is thus reduced and thus excess water is lost in urine

• Urine production almost stops as a result of serious blood loss

Loss of blood leads to reduction in blood pressure, this stops ultrafiltration in the Bowman’s capsules leading to reduction in urine production

• Presence of sugar in urine

This condition is called glycosuria and occurs when blood sugar levels rise above normal such that the filtered load exceeds what the kidney can absorb. This could be due to failure of the pancreas to secrete enough insulin in blood

• Feeling hungry faster in cold weather

On cold day there is high metabolic rate to supply heat to maintain body temperature hence need for high food consumption.