How and why we regulate blood flow

unit 3 week 11 lesson 1

why does the human body regulate blood flow?

to ensure that diff organs receive the right amount of blood base on their needs

does the size of the organ equal to greater blood flow?

no, the heart, brain, liver, and kidneys receive about 60% of our cardiac output at rest, despite only being about 5% of our total body mass

how does blood flow change during exercise?

Skeletal muscles require more o2 and nutrients so blood flow to muscles increase. As a result, organs like the digestive system might receive less blood so that more blood can go to our active muscles.

blood flow for prioritized organs

organs like the brain and heart are prioritized and therefore consistently receive a substantial amount of blood to maintain essential functions. This ever-changing distribution of blood is crucial for maintaining homeostasis and ensuring that each organ can perform its specific functions effectively.

blood flow=

p1- p2 x r ⁴ (radius) or

pressure/resistance

resistance relationship to blood flow

it decreases flow

why does blood encounter resistance as it moves thru the circulatory system

• primary factor is diameter of blood vessels; narrower vessels increase resistance, making it harder for blood to flow thru 

• viscosity of blood also has an effect, as thicker blood results in higher resistance, and reduces blood flow (hydration can affect viscosity)

• length of blood vessels— longer vessels provide more surface area for friction as blood moves along the endothelial cells lining blood vessel walls, friction increases resistance

equation of resistance

R= Ln/r⁴

R=resistance

L= length of our vessels

n is viscosity

r= radius of vessel