Q. Given below are four statements (a-d) regarding human blood circulatory system (a) Arteries are thick-walled and have narrow lumen as compared to veins (b) Angina is acute chest pain when the blood circulation to the brain is reduced (c) Persons with blood group AB can donate blood to any person with any blood group under ABO system (d) Calcium ions play a very important role in blood clotting Which two of the above statements are correct?
A) (a) & (d)
B) (a) & (b)
C) (b) & (c)
D) (c) & (d)
Explanation
[Solution from source] Arteries have thick muscular walls and a narrow lumen compared with veins, and Ca²⁺ ions are needed at several steps of the clotting cascade. Angina is chest pain caused by too little oxygen reaching the heart muscle, not the brain, and AB individuals are universal recipients, while O is the universal donor. Answer (1).
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.