Wednesday, January 29, 2020

Giraffe Brain

I love how you answer questions in your blogs! Here’s what my three-year-old niece wants to know, “How does blood get to a giraffe’s brain?”

According to the Smithsonian National Zoological Park, giraffes are the tallest living animals in the world. The giraffe's heart must have special mechanisms to enable it to pump blood up the animal's neck, 6 feet (2 meters) long neck to its brain. It’s a formidable task to pump blood at a pressure high enough to accomplish this. A giraffe's heart can weigh over 10 kg (22-24 pounds) and generate twice the blood pressure of other large mammals. (A human heart is about the size of its owner’s fist.) Having enough blood pressure to pump blood to the brain when the giraffe's neck is extended upward is one challenge. Another challenge occurs when a giraffe lowers its head, which could create grave risks due to excessive blood pressure. To counter this, according to the National Geographic, giraffes possess a rete mirabile, so called. It is a pressure-regulating system that restricts the amount of blood that rushes towards the brain when the giraffe lowers its head. More tomorrow.

No comments: