Answer to Question 1
Cold water is denser and has a higher viscosity than warm water. These factors, among others, profoundly influence marine life, resulting in the following differences between warm-water and cold-water species in the marine environment:
1. Floating organisms are physically smaller in warm waters than in colder waters. Small organisms expose more surface area per unit of body mass, which helps them maintain their position in the lower viscosity and density of warm seawater more easily.
2. Warm-water species often have ornate plumage to increase surface area, which is strikingly absent in the larger cold-water species.
3. Warmer temperatures increase the rate of biological activity, which more than doubles with an increase of 10C (18F). Tropical organisms apparently grow faster, have a shorter life expectancy, and reproduce earlier and more frequently than those in colder water.
4. There are more species in warm waters, but the total biomass of plankton in colder, high-latitude waters greatly exceeds that of the warmer tropics. Note that the high biomass of plankton in high-latitude regions is not directly caused by temperature and viscosity; it is only that these conditions are associated with the upwelling of nutrients, which in turn supports a vast biomass of phytoplankton.
Answer to Question 2
B
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