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Grizzly bears: As predators, bears keep down the numbers of several species, like moose and elk. They also carry and deposit seeds throughout the ecosystem. Bears that eat salmon will leave their dropping and the partially eaten remains that provide nutrients such as sulfur, nitrogen and carbon to the soil.
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A rainbow is caused by sunlight and atmospheric conditions. light enters a water droplet, slowing down and bending as it goes from air to denser water. The light reflects off the inside of the droplet, seperating into its component wavelengths-or colors when light exits the droplet, it makes a rainbow
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The answer is:
B. Worms consuming the blood from mammals.
Algae isn't causing any harm to the sloth, rather its providing it with camouflage to hide from predators. Both creatures benefits since the algae gets to eat any parasites and other things in the sloths fur, plus they get a free ride and home in the process. The sloth isn't harmed and is helped by the algae since it provides camouflage (mutualism).
Tree frogs aren't causing harm to the trees since they are only using them to hide from predators, the tree serves as protection for the frogs and aren't harmed in the process (commensalism).
Two fish protecting each other from predators aren't harming each other in any way, rather they are protecting each other from another animal that wants to eat them (mutualism).
The worms however are harming the mammals because they are consuming the mammals blood, this is parasitism since one animal is benefiting and the other is harmed.
Hope this helps! :)
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At times the virus activity appeared to sediment at a rate comparable with that of particles about 80 to 120 mµ in diameter, at other times at a rate comparable with that of particles about 10 mµ in diameter,
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