Axon diameter and degree of myelination determine nerve impulse conduction velocity.
true or false?

It is true, the bigger the diameter the slower the velocity of the impulse and myelin sheet helps the impulse travel in one direction.

c: warm water flows from the western tropical pacific toward south america. that should be the right answer! hope it .

the correct answer is: b. pantala flavescens, because these organisms would have a high level of genetic variation due to sexual reproduction.  

because involves two organisms (parents) whose genetic material combines, sexual reproduction leads to genetic variation in new generations of offspring. the offspring is an unique organism, with new genome, more protected with the higher ability to adapted. this process is fundamental to evolution.