Kidneys

Definition

Kidneys are two bean-shaped organs located in the posterior abdominal cavity. They play a crucial role in filtering blood to remove waste products and excess substances, maintaining overall fluid and electrolyte balance.

5 Must Know Facts For Your Next Test

1. Each kidney contains about one million nephrons, which are the functional units responsible for filtering the blood.
2. The kidneys regulate blood pressure through the renin-angiotensin-aldosterone system.
3. They produce erythropoietin, a hormone that stimulates red blood cell production in response to low oxygen levels.
4. The kidneys help maintain acid-base balance by excreting hydrogen ions and reabsorbing bicarbonate from urine.
5. Glomerular filtration rate (GFR) is a key indicator of kidney function, often measured to assess renal health.

Review Questions

• What is the primary function of nephrons within the kidneys?
• How do the kidneys contribute to regulating blood pressure?
• Which hormone produced by the kidneys stimulates red blood cell production?

Related terms

Nephron:

The functional unit of the kidney responsible for filtering blood and forming urine.

Glomerulus:

A network of capillaries located at the beginning of a nephron where blood filtration begins.

Renal Cortex:

The outer part of the kidney where most parts of nephrons are located.