<span>a. chemicals produced by neurons that function as hormones—neurohormones
b. chemicals that act locally on nearby cells—paracrine factors
c. chemicals secreted by presynaptic terminal—neurotransmiters
d. influences same cell type from which it is secreted—autocrine agent
e. chemical secreted into the blood by specialized cells; travels some distance to target tissues—endocrine hormones</span>
The answer to the question is A
Starfish have a unique form of digestion in the animal kingdom and a water-vascular system that allows the animal to breathe.
All your answers should be in this article:
http://animals.mom.me/feeding-respiration-starfish-6596.html
Answer:
The main difference is the presence of a nucleus.
Explanation:
One of the biggest differences is the presence of a nucleus with an envelope. This is very important because in eukaryotes it is present, but in prokaryotes, the genetic material is in the cytosol, although it's not exactly dispersed, it's slightly grouped. Also, the DNA in prokaryotes is organized in circular chromosomes while in eukaryotes it's organized in linear chromosomes arranged in an X shape. There are many more differences, but these two are the more important ones.