Marginalism is a theory of economics that attempts to explain the discrepancy in the value of goods and services by reference to their secondary, or marginal, utility. The reason why the price of diamonds is higher than that of water, for example, owes to the greater additional satisfaction of the diamonds over the water.
A large amount of circulating blood flows through the kidneys. Approximately 25% of the cardiac output or 1200 ml of blood per minute is received by the kidneys. One liter of urine is the end product of more than 1000 liters of circulating blood processed through the kidneys. large amount of circulating blood flows through the kidneys. Approximately 25% of the cardiac output or 1200 ml of blood per minute is received by the kidneys. One liter of urine is the end product of more than 1000 liters of circulating blood processed through the kidneys.
With the average heart rate of 72 beats per minute the heart will pump about 5 litres per ventricle, or about 10 litres total per minute. This is called the cardiac output. In a trained athlete the total cardiac output is about 20 litres. If we multiply the normal, non-athlete output by the average age of 70 years, we see that the cardiac output of the average human heart over a life time would be about 1 million litres, or about 250,000 gallons(US)!