They have two pairs of main nerve cords organized around a number of paired ganglia. while they don't have a "true brain"-- they have somewhat of a nervous system, composed of the two, or three pairs of nerve cords contained in the visceral mass.
<span>in the troposphere (the lower part of the atmosphere).</span>
Answer:

Explanation:
Blood vessels are vessels that carry blood through organs and tissues. The five types of blood vessels are: arteries, veins, arterioles, capillaries, and venules. The main function of blood vessels is to carry blood throughout the body.
The shape you will not see is a crescent . <span />
It's D RNA molecules transmit the genetic information from the nucleus to the ribosomes.