Answer:
chitin
Explanation:
chitin is a complex carbohydrates, similar to cellulose, that makes up organic structure, such as the cell walls of fungi and exoskeletons of insects and other arthropods.
Answer:
Explanation:
The barnacles are only able to attach themselves to surfaces in the water. Since the surface is limited, barnacles are attaching themselves to the other barnacles, crowding the rock. The muscles were not able to grow or attach themselves off the surface of the rock. Same thing with the mussels that are growing on the rock. So not only barnacles are crowding the rock, but Mussels as well are crowding the rock.
Photosynthesis and chemosynthesis Let me know if you want me to explain more in depth.