In a typical healthy adult human, approximately how many gallons of blood are present in the body?

• A. About 6 gallons
• B. About 0.5 gallon
• C. About 1.5 gallons
• D. About 3.5 gallons

Answer: (C)

Verified step by step guidance

1. Understand that the average blood volume in a typical healthy adult human is generally measured in liters or gallons and depends on factors such as body size and sex.
2. Recall that the average blood volume for an adult is approximately 7% to 8% of their total body weight.
3. Convert this percentage into volume by considering an average adult weight (for example, around 70 kg or 154 lbs) and using the density of blood, which is close to that of water (about 1 kg/L).
4. Calculate the approximate volume in liters by multiplying the body weight by the percentage of blood volume (e.g., 70 kg × 0.07 = 4.9 liters).
5. Convert the volume from liters to gallons using the conversion factor: 1 gallon ≈ 3.785 liters, to find the approximate number of gallons of blood in the body.