They are the energy base of the food chain for all aquatic organisms, without them all aquatic organisms would most likely parish.
Sponges have specialized cells and an endoskeleton, but they lack tissues and body symmetry. ... They include jellyfish and corals, both of which have radial symmetry. All cnidarians have nematocysts, and many are bioluminescent. They may exist in medusa and/or polyp form.
A. Veins
B. <span>Arteries
C. </span><span>Capillaries</span>
All the cells in a person's body have the same DNA and the same genes. However, the difference between cells in different tissues and organs is that the "expression" of the genes differs between cells. ... For example, liver cells have different proteins than skin cells, even though their DNA is the same......this is a google search i hope it helps