Heart Heroes: Fun Circulatory Quiz for Curious Kids!

Explore blood, hearts, and vessels with easy, playful questions. Learn cool facts and become a circulatory whiz—perfect for kids 6+ who love to discover!

  1. What pumps blood through your body?
    1. Brain
    2. Lungs
    3. Stomach
    4. Heart
  2. What color is oxygen-rich blood inside the body?
    1. Blue
    2. Red
    3. Green
    4. Yellow
  3. Which tiny tubes carry blood to cells?
    1. Nerves
    2. Arteries
    3. Veins
    4. Capillaries
  4. What carries blood back to the heart?
    1. Veins
    2. Arteries
    3. Capillaries
    4. Lymph
  5. What tiny cells help stop bleeding?
    1. Platelets
    2. Red cells
    3. White cells
    4. Plasma
  6. Which liquid part of blood carries nutrients?
    1. Lymph
    2. Serum
    3. Plasma
    4. Saliva
  7. What do red blood cells carry to the body?
    1. Food
    2. Oxygen
    3. Germs
    4. Heat

Answers and explanations

  1. Question: What pumps blood through your body?
    Answer: Heart
    Explanation: The heart is a strong muscle that squeezes to push blood all around your body; lungs do breathing, not pumping.
  2. Question: What color is oxygen-rich blood inside the body?
    Answer: Red
    Explanation: Blood with lots of oxygen looks bright red; people sometimes think it's blue in veins, but it only looks bluish through skin.
  3. Question: Which tiny tubes carry blood to cells?
    Answer: Capillaries
    Explanation: Capillaries are the smallest blood vessels where oxygen and food pass to cells; arteries and veins are bigger and carry blood farther.
  4. Question: What carries blood back to the heart?
    Answer: Veins
    Explanation: Veins bring used blood back to the heart; some people mix them up with arteries, but arteries carry blood away from the heart.
  5. Question: What tiny cells help stop bleeding?
    Answer: Platelets
    Explanation: Platelets clump together to plug cuts so you stop bleeding; red blood cells carry oxygen, so they aren't for clotting.
  6. Question: Which liquid part of blood carries nutrients?
    Answer: Plasma
    Explanation: Plasma is the watery part that transports nutrients and wastes; cells live in plasma, so it's not a cell itself.
  7. Question: What do red blood cells carry to the body?
    Answer: Oxygen
    Explanation: Red blood cells hold hemoglobin which carries oxygen to cells so we have energy; they don't carry germs—that's what white blood cells fight.