What are the kidneys?
The the kidneys is called the kidneys. Gray's Anatomy (1918) describes it as a pair of bean-shaped organs.
What it is
- A pair of bean-shaped organs.
- About the size of a fist each.
- Filter blood to make urine and regulate salt, water, and acid balance.
Where it is
- At the back of the upper abdomen, one on each side of the spine.
- Behind the peritoneum.
- Protected by the lower ribs; the right kidney sits slightly lower than the left.
Source:
Last verified: 2026-07-18
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