What does dialysis do?

Filters blood when kidneys fail

Human Kidneys Quiz: 10 Questions That Test What You Know

This human kidneys quiz covers where the kidneys are, how nephrons filter blood, how urine is made, water balance, kidney stones, dialysis and the first kidney transplant. Ten questions test what you know about the body's filtering organs.

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🎯 Daily Trivia Challenge • 🧠 10 Questions • ⏱️ 150 Seconds

Question 1 / 10 Time: 150s

Count
How many kidneys do most people have?
Shape
What shape are kidneys?
Location
Where are the kidneys located?
Units
What are the tiny filtering units of the kidney called?
Filter
About how much blood do the kidneys filter each day?
Output
What waste product do kidneys remove in urine?
Bladder
Which tubes carry urine from the kidneys to the bladder?
Dialysis
What does dialysis do?
Transplant
When was the first successful kidney transplant between identical twins?
Hormones
Which hormone made by the kidneys helps produce red blood cells?

Explanations: answer key for all 10 questions

Q1: How many kidneys do most people have?
Answer: Two
People can live healthy lives with just one working kidney.
Q2: What shape are kidneys?
Answer: Bean-shaped
Each is about the size of a fist.
Q3: Where are the kidneys located?
Answer: Near the back, below the ribs
They sit on either side of the spine.
Q4: What are the tiny filtering units of the kidney called?
Answer: Nephrons
Each kidney has about a million of them.
Q5: About how much blood do the kidneys filter each day?
Answer: About 180 liters of fluid
Most of it is reabsorbed back into the body.
Q6: What waste product do kidneys remove in urine?
Answer: Urea
Urea comes from breaking down proteins.
Q7: Which tubes carry urine from the kidneys to the bladder?
Answer: Ureters
The urethra carries urine out of the body.
Q8: What does dialysis do?
Answer: Filters blood when kidneys fail
Machines do the kidneys' work.
Q9: When was the first successful kidney transplant between identical twins?
Answer: 1954
Joseph Murray led the surgery in Boston.
Q10: Which hormone made by the kidneys helps produce red blood cells?
Answer: Erythropoietin (EPO)
It signals bone marrow.

Human Kidneys Quiz – The Body's Filters

The kidneys are two bean-shaped organs near the back, just below the ribs. Each contains about a million tiny filters called nephrons, which clean the blood by removing waste and extra water to make urine.

Every day the kidneys filter roughly 180 liters of fluid, but return almost all of it to the blood, producing only about one to two liters of urine. They also balance salts, control blood pressure and make hormones that boost red blood cell production and keep bones healthy.

When kidneys fail, dialysis machines can filter the blood, and kidney transplants can restore function. The first successful transplant was performed in 1954. Drinking enough water and managing blood pressure and blood sugar help keep kidneys healthy.

What This Quiz Teaches

This quiz is for students learning about the kidneys.

How many kidneys we have
What nephrons do
How much fluid is filtered
What dialysis is
When transplants began

Did You Know?

Kidney stones are hard mineral deposits.
Kidneys receive about a fifth of the heart's output.
Adrenal glands sit on top of the kidneys.
Urine color reflects hydration.
Kidney transplants are the most common organ transplants.