Answer:
The heart is not strong enough by itself to get the blood back up the veins in your legs and back to your heart. So it is a combination of blood pressure from the heart's pumping action, the valves, and muscle movement that gets the blood up the legs against gravity.It is often concluded, therefore, that the heart works only against the viscous resistance of the system, not against gravity, even in vascular loops above the heart in which the siphon principle operates.
How do we detect the taste of different types of food we eat?
Taste buds have very sensitive microscopic hairs called microvilli (mykroVILLeye). Those tiny hairs send messages to the brain about how something tastes, so you know if it's sweet, sour, bitter, or salty.
The greatest danger to your brain is not the possibility that a large portion is going on unused. Rather, the greatest dangers are stroke, Alzheimer's disease, and tumors. The best ways to protect yourself from such risks include eating healthy, exercising, and getting enough rest
Step-by-step explanation:
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