DNA, Do you want the rest of Lesson 16: The Fossil Record Biology B Unit 1: Evolution Quick Check?
If I am reading this right, I would say that that fiber would be a nerve.
I believe your answer is Blood
They need to be able to sense incoming threats
The answer is conduction. This is a form of heat transfer due to temperature difference, through direct contact with objects that are touching, in which the hotter object passes heat to the cooler objects by molecular collisions. Convection is another form of heat transfer in which heat travels through fluids while radiation through empty spaces.
