Notes, summaries, assignments, exams, and exercises for Biology for Secondary education

Understanding Kidney Function

As capillaries exit organs, they converge into larger blood vessels, veins, which eventually return the blood to the heart at the right atrium.

Abnormal Kidney Function:

An individual's kidneys are unable to remove waste, the medical treatment known as hemodialysis. Use a dialysis machine 'artificial kidney' is only temporary, until the patient recovers normal kidney function or receives a kidney transplant. Blood is put in close contact with a special solution similar to blood plasma. The semipermeable membrane allows urea and other waste materials to exit the blood and prevents the escape of blood cells.

Painful Stones:

The substances transported in the urine can trigger the formation of crystals, commonly referred...

How Kidneys Work: Filtration and Waste Elimination

Solid waste products need to be dissolved in water to be eliminated from the body.

The Nephron: The Kidney's Functional Unit

Each kidney contains over a million functional units called nephrons, where the filtering process takes place.

Parts of the Nephron

• Bowman’s Capsule: Surrounds a tiny network of capillaries.
• The Tubule: Shaped like a handle, several nephrons empty into a large tube called a collecting duct.
• The Collecting Duct: Moves urine into the renal pelvis.

Kidney Function Process

1. Blood moves through the capillary networks where filtration occurs. Small molecules such as water, salts, glucose, and urea exit the bloodstream and enter Bowman’s capsule, forming the filtrate.
2. Some of the molecules