The Story of Mika, pt. 8

Ecturians also have a different internal structure to humans. They have four small, two chambered hearts set at the four corners of the torso. They also have the necessary ganglia in their brains that allow them to interact with the TARDIS telepathic circuits. There are also various other internal organs unique to the Ecturian.

Ecturians also have an extended life span because of the added plant DNA. Whereas they would live to just about 110 before on average, now they live to be over 1500 years naturally. With Mika’s altered DNA, there is no way of knowing what her natural life span would be, but with the timelord’s added 12 regenerations, she is currently over 3000 earth years old and could live to be ten times that old.