Final answer:
The viscosity of blood, which is its thickness or resistance to flow, significantly affects blood pressure. When hematocrit increases, the blood becomes more viscous and the resistance to blood flow increases, leading to higher blood pressure. Conversely, when hematocrit decreases, the blood becomes less viscous and the resistance to blood flow decreases, resulting in lower blood pressure.
Step-by-step explanation:
The viscosity of blood, which is its thickness or resistance to flow, significantly affects blood pressure. When hematocrit increases, meaning there is a higher percentage of red blood cells in the blood, the blood becomes more viscous or thicker. This increased viscosity leads to increased resistance to blood flow, which in turn increases blood pressure. Conversely, when hematocrit decreases, the blood becomes less viscous and the resistance to blood flow decreases, resulting in lower blood pressure.