Are especially important because they are involved in a variety of processes, such as cell signaling, immune response, and enzyme activity.
a.
nucleic acids
b.
carbohydrates
c.
proteins
d.
lipids

volcanoes (an event in the geosphere) release a large amount of particulate matter into the atmosphere. these particles serve as nuclei for the formation of water droplets (hydrosphere). rainfall (hydrosphere) often increases following an eruption, stimulating plant growth (biosphere).

answer; the tunica intima also called tunica interna, consists of elastic fibers,connective tissue and smooth muscle cells;