Answer:
a model that illustrates the organelles of cells
the importance of this procedure is to get a set of data to compare your other test results to, like when they are active
Fresh water is any body of water with a low salt concentration. Organisms in fresh water various challenges which includes; Osmotic concentration such that fresh water is permanently dilute and most cells cannot function at this concentration of ions. Varying temperatures, variation in oxygen levels and reproduction and life cycle due to permanence of habitat and physiological difficulty of regulating osmotic concentration in larvae and juveniles.
The third and last option is correct.
Species in the past (referring to dinosaurs) were more massive.
levels where higher in the past, which meant that plants prospered during that time since they had a easy access to food. That contributes to the fact that herbivores could grow bigger because there was more food. Which in turn, increases the size of early carnivores which eat bigger herbivores.
Hope it helped,
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