Hydrothermal Animals
In order to survive high sulfide concentration, hydrothermal organisms have developed specific ways to deal with sulfide. An effective transport system is present to allow sulfide to be taken up front the ambient seawater and carried to the bacterial aymbionts without dangers of spontaneous oxidation of the sulfide or poisoning of respiration by the sulfide, then the bacterial endosymbionts performs the initial oxidation of sulfide and the subsequent oxidation steps. The initial oxidation step is important because it prevents accumulation of free sulfide in the hydrothermal animals. On the other hand, it also helps generating ATP. [1]
Planktonic Animals
Planktonic animals have several adaptions that allow them to avoid predation, conserve energy, and process nutrients efficiently. They have a small body with complex shapes to increase surface area-to-volume ratio that facilitates rapid exchange of gases by diffusion. It also creates a large frictional resistance--an adaption that allows the organism to sink at a slower pace. In addition, their body shape and size allows for rapid excretion of wastes across the body surface, nutrient absorbing, and light trapping to produce energy. Often, the organism's shape itself will prevent it from sinking; plankton can be flattened or shape themselves to sink in a spiral motion. Projections, such as long projections and spines, not only aid in buoyancy, but also prevent predation. Planktonic animals also typically have buoyancy aids to help the animal in motion--these include buoyant oil droplets, gas-filled vesicles, and excretion of heavy ions to retain ions lighter in density. [2] Organisms may have bioluminescent skins for camouflage as well, with such a small shape, the animal lacks many defense mechanisms against predators and relies on camouflage techniques.
In order to survive high sulfide concentration, hydrothermal organisms have developed specific ways to deal with sulfide. An effective transport system is present to allow sulfide to be taken up front the ambient seawater and carried to the bacterial aymbionts without dangers of spontaneous oxidation of the sulfide or poisoning of respiration by the sulfide, then the bacterial endosymbionts performs the initial oxidation of sulfide and the subsequent oxidation steps. The initial oxidation step is important because it prevents accumulation of free sulfide in the hydrothermal animals. On the other hand, it also helps generating ATP. [1]
Planktonic Animals
Planktonic animals have several adaptions that allow them to avoid predation, conserve energy, and process nutrients efficiently. They have a small body with complex shapes to increase surface area-to-volume ratio that facilitates rapid exchange of gases by diffusion. It also creates a large frictional resistance--an adaption that allows the organism to sink at a slower pace. In addition, their body shape and size allows for rapid excretion of wastes across the body surface, nutrient absorbing, and light trapping to produce energy. Often, the organism's shape itself will prevent it from sinking; plankton can be flattened or shape themselves to sink in a spiral motion. Projections, such as long projections and spines, not only aid in buoyancy, but also prevent predation. Planktonic animals also typically have buoyancy aids to help the animal in motion--these include buoyant oil droplets, gas-filled vesicles, and excretion of heavy ions to retain ions lighter in density. [2] Organisms may have bioluminescent skins for camouflage as well, with such a small shape, the animal lacks many defense mechanisms against predators and relies on camouflage techniques.