Red Blood Cells Quiz: Hemoglobin, No Nucleus and 120 Days

This red blood cells quiz rides through the bloodstream. Play 10 interactive questions on hemoglobin and its iron, the biconcave disc shape, why mammal red cells lose their nucleus, a lifespan of about 120 days, production in bone marrow, the spleen recycling old cells, the role of the kidney hormone EPO, anemia and why red cells are the most common cells in the body.

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

Question 1 / 10 Time: 150s

Job
What is the main job of red blood cells?
Hb
Which protein carries oxygen in red blood cells?
Iron
Which metal is in hemoglobin?
Shape
What shape are red blood cells?
Nucleus
What do mature human red blood cells lack?
Life
How long does a red blood cell usually live?
Made
Where are red blood cells made in adults?
Spleen
Which organ helps remove old red blood cells?
EPO
Which hormone from the kidneys boosts red cell production?
Anemia
What is a shortage of red blood cells or hemoglobin called?

Explanations: answer key for all 10 questions

Q1: What is the main job of red blood cells?
Answer: Carrying oxygen
They also carry some carbon dioxide.
Q2: Which protein carries oxygen in red blood cells?
Answer: Hemoglobin
It contains iron.
Q3: Which metal is in hemoglobin?
Answer: Iron
It binds oxygen.
Q4: What shape are red blood cells?
Answer: Biconcave discs
Like a dented doughnut.
Q5: What do mature human red blood cells lack?
Answer: A nucleus
More room for hemoglobin.
Q6: How long does a red blood cell usually live?
Answer: About 120 days
Then it is recycled.
Q7: Where are red blood cells made in adults?
Answer: Bone marrow
Billions are made every day.
Q8: Which organ helps remove old red blood cells?
Answer: The spleen
The liver helps too.
Q9: Which hormone from the kidneys boosts red cell production?
Answer: Erythropoietin
It is often called EPO.
Q10: What is a shortage of red blood cells or hemoglobin called?
Answer: Anemia
It can cause tiredness.

Oxygen Carriers of the Blood

Red blood cells carry oxygen from the lungs to the body using hemoglobin, an iron-containing protein that also gives blood its red color. They are biconcave discs, like dented doughnuts, which gives a large surface for gas exchange and lets them squeeze through tiny capillaries.

Mature human red blood cells have no nucleus, leaving more room for hemoglobin. They live about 120 days before the spleen and liver remove them and recycle their iron. In adults, bone marrow makes billions of new red cells every day, boosted by erythropoietin, or EPO, a hormone from the kidneys.

Red blood cells are the most common cells in the human body. A shortage of red cells or hemoglobin is called anemia and can cause tiredness and paleness, often linked to low iron.

What This Quiz Teaches

Body science fans will enjoy these questions.

What red blood cells do
How hemoglobin works
Why they lack a nucleus
How long they live
What anemia is

Did You Know?

Bird red blood cells keep their nucleus.
Altitude training raises red cell counts.
Blood donation replaces cells within weeks.
Iron-rich foods help hemoglobin.
Camels have oval red blood cells.