Question

The blood of a normal healthy adult rat contains 5 million red blood cells (RBCs) per microliter of blood. Each deciliter of blood contains 15 grams of hemoglobin. Each RBC contains 250 million molecules of hemoglobin (a fairly close approximation for a healthy adult retired breeder female rat). Suppose you have 8.56 mL of blood drawn from a healthy female retired breeder rat, then how many RBCs are in this blood sample?

Answer 1

There are 4.28×10^10 RBCs in the blood sample.

Step-by-step explanation:

Concentration of blood = 5×10^6 RBC/10^-6 L = 5×10^12 RBC/L of blood

Volume of blood sample = 8.56 mL = 8.56/1000 = 0.00856 L

Number of RBCs = concentration of blood × volume of blood sample = 5×10^12 RBC/L × 0.00856 L = 4.28×10^10 RBCs