Answer:
C). viscosity increases with increasing length of the blood
Explanation:
Systemic vascular resistance (SVR) refers to the resistance to blood flow offered by all of the systemic vasculature, excluding the pulmonary vasculature. This is sometimes referred as total peripheral resistance (TPR).
Some factors that decrease blood flow and increase resistance include increased viscosity of the blood, increased length of the blood vessel and decreased radius of the blood vessel. Blood vessels - and in particular, the more muscular arteries - are often the source of resistance.
What determines resistance are:
1. Resistance is proportional to LENGTH (L) of the tube (blood vessel)
-Resistance INCREASES as length increases
2. Resistance is proportional to VISCOSITY, or thickness, of the fluid (blood)
-Resistance INCREASES as viscosity increases
3. Resistance is inversely proportional to tube RADIUS to the fourth power
4. Resistance DECREASES as radius increases
