With reference to the blood in a normal person, which one of the following statements is correct?
- ACompared to arteries, veins are less numerous and hold less of the body’s blood at any given time
- BBlood cells constitute about 70 per cent of the total volume of the blood
- CWhite Blood Cells (WBC) are made by lymph nodes only
- DThe blood has more platelets than WBCCorrect
Explanation
The correct option is D because of the relative count of different blood components.
In a healthy human, a microliter of blood contains approximately 150,000 to 450,000 platelets, whereas the White Blood Cell count is much lower, ranging from 4,500 to 11,000. Therefore, platelets significantly outnumber WBCs.
Other options are incorrect because: A) Veins are more numerous and act as a reservoir, holding about 65 to 70 percent of the body blood. B) Blood cells make up about 45 percent of the blood volume, while plasma makes up the remaining 55 percent. C) WBCs are primarily produced in the bone marrow, though some types mature or multiply in the lymph nodes and spleen.

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