Adult giraffes can be up to 20 ft. tall, and thus require special adaptations to maintain appropriate blood pressure. One adaptation is the rete mirabile, a group of blood vessels that form a web or net-like structure to slow blood flow.The giraffe, as the tallest living land animal, has several adaptations for its height. To prevent blood from pooling in the head when it bends down to drink, the jugular veins of a giraffe have multiple one-way valves. Furthermore, a web of arteries and veins in the neck called the rete mirabile ("wonderful net") slows the flow of blood into the brain. These specializations of the ________ act as mechanisms to maintain ________.

A. circulatory system; blood pressure homeostasis
B. nervous system; temperature homeostasis
C. circulatory system; pH homeostasis
D. nervous system; homeothermy


Answer: A

Biology & Microbiology

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