pressure and velocity in blood vessels

[bryanwong]

in the textbook,
it says,
"the blood pressure is even lower when it reaches the venules and the vein due to the friction of the capillary wall."

However,later it says
"The velocity of blood rises slowly again later since the cross sectional area of veins is smaller than capillaries."

Why does't the friction of the capillary wall slows down the blood flow?

Also, can someone tell me the relationship between friction ,pressure and velocity in simple words but not in physics?

Preparing for exam now,thanks for your help

[bryanwong]

p.s. The rate of blood flow decreases when pressure drops
so why the pressure drops while the velocity increases when the blood reaches the venules and the veins ?

[JackBean]

liquids are basically incompressible, thus if you lower radius of your pipeline, you need to increase speed of the liquid, otherwise it had to accumulate somewhere.