1. Waste products
When we eat and breathe, we get beneficial elements, but we also get harmful waste products that we must expel. The wastes products are four:
- Feces containing the useless remnants of the food that we eat. They are expelled from the large intestine through the anus (see the subject of the digestive tract).
- Carbon dioxide (CO2) are produced in the cells, when the nutrients burn. We expel it from the lungs through the mouth and nose (see the subject of the respiratory system).
- Urine containing waste products that goes to the blood. It is eliminated through the urinary system, through the urethra.
- The sweat produced by the sweat glands and it is expelled through the pores of the skin.
2. Indicate the appropriate waste product: feces, carbon dioxide, urine or sweat