Arteries are blood vessels. Most carry oxygen-rich blood from the heart to various organs and tissues. Arteries are a part of the circulatory system, along with the heart and other blood vessels. The ...

There are three types of blood vessel: arteries, veins and capillaries. The heart is a muscular organ that pumps blood around your circulatory system. The circulatory system is the heart and all the ...

Quirks and Quarks19:53Our planet’s circulatory system depends on animals eating, excreting and expiring From the tiniest insects to the largest whales, biologist Joe Roman says animals play an ...