BIO Standing on your head. (a) When you stand on your head, what is the difference in pressure of the blood in your brain compared with the pressure when you stand on your feet if you are $1.85 \mathrm{~m}$ tall? The density of blood is $1060 \mathrm{~kg} / \mathrm{m}^{3}$. (b) What effect does the increased pressure have on the blood vessels in your brain?