Concept Check

• If the hematocrit value of a woman's blood is 42, what percentage of red blood cells is present in her blood?

  The hematocrit value closely approximates the percentage of red blood cells; thus, red blood cells account for 42 percent of her blood volume
• How does the shape of red blood cells aid in blood flow?

  Red blood cells have the ability to stack and create a roulaeu, which can pass through a tiny blood vessel more easily than could many separate red blood cells. In addition, red blood cells are flexible, which allows them to squeeze through small capullaries.
• What type of white blood cells appear in the greatest number in an infected cut?

  Neutrophils appear in the greatest number in an infected cut
• What is the function of the granules in basophils?

  The granules contain histamine; its release promotes inflammation at the injury site