1. What do platelets do?
- Produce antigens and antibodies
- Help clot the blood
- Hold food
- Carries oxygen
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Other questions in this quiz
2. What are valves (in a blood vessel) used for?
- To direct the flow of blood
- To stop the blood from flowing
3. Do red blood cells have a nucleus?
- Only the white ones
- Only some
4. True or false, veins carry deoxygenated blood
5. What is plasma mostly made of?
- Red blood cells
- Nitrate ions