The dark brown color of a penny is most likely oxidation, which occurs when the copper in the penny comes in contact with oxygen.<span> </span>
<span>The answer would be: host symbionts with colorful photosynthetic pigments
Coral can host symbionts that will help in their growth. There are algae that could live on the coral surface, giving them some of the energy from photosynthesis and help in calcification while the coral protects the algae. </span>The symbiosis will be formed when nearby algae attach to the corals. A stress on the coral can cause the algae to eject the algae.
The upper arm bone is the claveical
