This websight will tell u what u need to know sorry if iam no help but this will help some what.... http://www.ushistory.org/civ/8a.asp
I. They they don't need to have a gas exchange system so they just breathe or respire through diffusion.
diffuse in the oxygen and diffuse out the carbon dioxide.
this happen if they were respiring aerobically, with the presence of oxygen.
Answer:
Explanation:
overproduction. all species tend to have more than two offspring per pair.
variation. all populations have variable traits.
competition. each organism competes for limited resources.
survival of the fittest. those best suited to the environment surive.
reproduction. ...
specification.
All animals have all the characteristics of life unless there dead.
What is cell specialization?
Answer: cell specialization is an adaptation to do a particular job in a cell
