Digestive and Excretory Systems Chapter 49 Digestive and Excretory Systems

Nutrition Label

Vitamins

Trace Elements

USDA Food Pyramid

Digesting Food Molecules

Digestive System in the Human Body

Inside the Human Coelom

Cross Section of the Small Intestine

Human Kidney Structure

How a Kidney Machine Works

Excretory System in the Human Body

A meal may take up to three days to pass through your digestive system A meal may take up to three days to pass through your digestive system. It spends about three hours in your stomach.

About 150 liters (33 gallons) of fluid pass through your kidneys every day. But 99% of this cleaned and goes back into your blood. In their lifetimes, adults pass about 40,000 liters (8,800 gallons) of urine. This is enough to fill 500 bath tubs.

About 96% of urine is water About 96% of urine is water. It also contains some waste salts and a substance called urea. Urea is made during the breakdown of proteins in your liver. Urea may also leave your body in sweat. If urea builds up in your body, it is a sign that your kidneys are not working properly. Kidney failure can be fatal if it is not treated quickly.