Urine

Definition

Urine is a liquid byproduct of metabolism that is excreted by the kidneys. It consists of water, urea, salts, and other waste products.

5 Must Know Facts For Your Next Test

1. Urine formation involves three main processes: filtration, reabsorption, and secretion.
2. The primary function of urine is to remove waste products and excess substances from the bloodstream.
3. Urine production helps maintain homeostasis by regulating the volume and composition of body fluids.
4. The color and concentration of urine can vary based on hydration levels, diet, and health conditions.
5. The average adult produces about 1 to 2 liters of urine per day.

Review Questions

• What are the three main processes involved in urine formation?
• How does urine contribute to maintaining homeostasis in the body?
• What factors can influence the color and concentration of urine?

Related terms

Kidney: The organ responsible for filtering blood to produce urine.

Nephron: The functional unit within the kidney where urine is produced.

Ureter: The duct through which urine passes from the kidney to the bladder.