Enter your Name:   Enter your E-mail Address:  Define the following terms: 01a. Mesopelagic zone 01b. Photophores 01c. Hydrothermal vent 01d. Bioluminescence 01e. Chemosynthesis 02. As depth increases in the ocean, the abundance of life and the quantity of food decrease. Explain why this is so. 03. Suppose you drop a thermometer into the ocean and monitor its temperature reading as it sinks. You suddenly notice a sharp drop in the temperature. In which zone of the ocean is the thermometer? 04. Suppose the thermometer in the question above has a pressure-sensitive device as well. Suppose you continue to watch both the pressure and the temperature as the devices continue to sink. Assuming you already saw the sharp drop in temperature mentioned in the previous problem, which would you expect to change more drastically after that point: pressure or temperature? 05. How do mesopelagic fishes compare in size to their epipalgic counterparts? 06. Why do most mesopalgic fishes have a broad diet? 07. What physical features are typically possessed by mesopelagic fish that find their food through vertical migration? 08. How are ventrally located photophores helpful in camouflage? 09. What physical feature differentiates the deep sea from the mesopelagic? 10. What two chemicals must an organism produce in order to perform bioluminescence? What does each chemical do? 11. As compared to an organism's ability to get food in the deep sea water column, how difficult is it for a deep sea floor individual to find food? 12. The figure below shows a food web for the deep sea floor. Fill in the blanks labeled a-c. 12. a-c 13. A marine biologist studied a sunken whale carcass at a specific location on the deep sea floor along with the organisms living on it. Just two years later, scientists returned to the same location to discover bare ocean floor. What happened to this community?