Most axons of vertebrates are enclosed in a myelin sheath, which increases the speed of impulse transmission; some large axons may transmit impulses at speeds up to 90 metres (300 feet) per second.
Lynda Carter Wonder Woman's STILL SUPER HOT. 61-year-old Lynda Carter -- famous for playing Wonder Woman on the '70s show -- must really have super powers ... because she's still scorchin' hot.
Jay-Z (Shawn Carter) is 46 years old. He was born on December 4, 1969, and is originally from Marcy Houses - a housing project in Brooklyn, New York. He married singer Beyonce Knowles in 2008. Jay-Z (Shawn Carter) is 46 years old. He was born on December 4, 1969, and is originally from Marcy Houses - a housing project in Brooklyn, New York. <br /> He married singer Beyonce Knowles in 2008.