Giraffe have unusually high heart rates for their size, at 150 beats per minute. When the animal lowers its head the blood rushes down fairly unopposed and a rete mirabile in the upper neck, with its large cross sectional area, prevents excess blood flow to the brain. When it raises again, the blood vessels constrict and direct blood into the brain so the animal does not faint. The jugular veins contain several (most commonly seven) valves to prevent blood flowing back into the head from the inferior vena cava and right atrium while the head is lowered. Conversely, the blood vessels
Returning to the 'A' Returning to the 'A' Returning to the 'A' () is a 2011 Kazakhstani drama film directed by Egor Konchalovsky. The film was selected as the Kazakhstani entry for the Best Foreign Language Film at the 84th Academy Awards, but it did not make the final shortlist. A young, creative team of TV Russian and Kazakh cinematographers are sent on a perilous journey from Almaty to Afghanistan to film a documentary film "In the Footsteps of Alexander the Great". They are accompanied by a man who once fought on the land of Afghanistan and lost a leg in the fighting -