why does blood run inside the body and why can't a human fly???

Answer 1

God made it that way and we are too heavy

Answer 2

Blood is essentially nature's way (or one of nature's ways, rather) of distributing oxygen and nutrients among cells in an organism. it turns out that many nutrients as well as oxygen-bonding proteins move around fairly efficiently in an aqueous solution. So having a liquid that contains it all is pretty handy. But the problem with liquids is that they tend to run all over the place unless bounded mechanically. So most animals have some sort of system -- such as a compound layer of thin cells known as "skin" -- that keeps blood from leaking out and flowing all over tarnation.

As for flying, you CAN fly thanks to two amazing adaptations -- the remarkable human brain and the human social system. The former has made it possible for man to develop mechanical air transportation, and the latter has made it possible for individuals who do not possess their own flying devices to exchange resources for temporary passage on the devices of others.

Answer 3

Because it's too messy for blood to run outside the human body. Humans can fly, but only off the top of high buildings. It's the landing that kills em.

Answer 4

Blood is pumped by the heart and to fly would require that humans had a very large breastbone- probably over 5 feet wide- to hold sufficient muscle mass to flap wings and generate lift.

Answer 5

Are you serious?

Blood runs because your heart is always pumping it. Blood carries oxygen from the lungs to all the cells of your body, and without the oxygen your cells cannot release the stored energy they need to function. Also it carries other vital nutrients throughout the body.

And you can't fly because you don't have wings or any other biological mechanism that would allow you to overcome the pull of gravity.

Answer 6

Blood flows through the circulatory system due to the heart and blood vessels. Humans cannot fly because we are more dense that air and we do not have large surface area wings.

Answer 7

Blood runs inside becasue we don't want it going everywhere, we need it pumping through our system. We can't fly becasue we are too heavy and lack of wings.
Birds that fly have hollow bones.

Answer 8

(a) because if it walked it would never get all the way around in time,
and (b) because the teleportation device only works in the movies or on the Simpsons. The real question, of course, is "Why _can_ a house fly?"

Answer 9

well if the blood is on the outside it would get kinda messy.
humans can fly, in planes and other things like that.

Answer 10

Blood is in your body keep you alive. people are too heavy to fly.

Answer 11

Blood flow is a closed system and you do not have a keel shaped breastbone.