Theodor w. engelmann illuminated a filament of algae with light that passed through a prism, thus exposing different segments of algae to different wavelengths of light. he added aerobic bacteria and then noted in which areas the bacteria congregated. he noted that the largest groups were found in the areas illuminated by the red and blue light.
what did engelmann conclude about the congregation of bacteria in the red and blue areas? a) bacteria released excess carbon dioxide in these areas. b) bacteria congregated in these areas due to an increase in the temperature of the red and blue light. c) bacteria congregated in these areas because these areas had the most oxygen being released. d) bacteria are attracted to red and blue light and thus these wavelengths are more reactive than other wavelengths. e) bacteria congregated in these areas due to an increase in the temperature caused by an increase in photosynthesis.

Hunting in the darksome fish rely on senses beyond sight. in the darkness of the marianas trench, a fish called the rattail has an extremely sensitive sense of smell. the fish uses scent, rather than sight, to steer toward food. once it's near food, the rattail uses a special organ on the bottom of its chin to guide itself by feel.marine snowone staple of the deep sea diet is "marine snow," flakes of organic, edible substances that sink down from the upper ocean. animals at the ocean's bottom find sustenance in everything from the bodies of dead creatures to fecal matter. marine snow is diverse enough to support numerous species. for instance, several species of snails and worms feed exclusively on deceased whales.microorganismsthe deep sea is an intricate ecosystem, and even the ocean floor itself plays a part. hydrothermal vents are cracks in the sea floor where erupting magma mixes with ocean water to produce plumes of hot, sulfur-rich chemicals. some microbes can use these chemicals for energy, sustaining their existence and that of the animals who depend on their roles in the deep sea food chain.