Best Biology Topics

✅ Circulatory System – 50 Quiz Questions
1. What is the main function of the circulatory system?​
A) Digestion​
B) Transportation​
C) Respiration​

✅
D) Excretion​
Answer: B



2. The heart is divided into how many chambers?​
A) 2​
B) 3​
C) 4​

✅
D) 5​
Answer: C



3. Which chamber receives oxygenated blood from the lungs?​
A) Right atrium​
B) Left atrium​
C) Right ventricle​

✅
D) Left ventricle​
Answer: B



4. Which vessel carries deoxygenated blood from the body to the heart?​
A) Pulmonary artery​
B) Aorta​
C) Vena cava​

✅
D) Pulmonary vein​
Answer: C



5. What type of blood do arteries generally carry?​
A) Deoxygenated​
B) Mixed​
C) Oxygenated​

, ✅
D) Lymph​
Answer: C



6. The largest artery in the body is the:​
A) Pulmonary artery​
B) Aorta​
C) Carotid artery​

✅
D) Renal artery​
Answer: B



7. The pulmonary veins carry blood to the:​
A) Lungs​
B) Right atrium​
C) Left atrium​

✅
D) Right ventricle​
Answer: C



8. Blood is composed of:​
A) Plasma only​
B) Red and white cells only​
C) Plasma, cells, and platelets​

✅
D) Nutrients and oxygen​
Answer: C



9. Which component of blood helps in clotting?​
A) Plasma​
B) Red blood cells​
C) Platelets​

✅
D) White blood cells​
Answer: C



10. Which blood cells fight infections?​
A) Erythrocytes​
B) Platelets​
C) Neurons​