HEL An investigation was designed to determine how freshwater fich maintain homeostasis within their environment. It was observed that the concentration of substances in the fichis was much higher than the
concentration of substances in ponds, les, and streams and that freshwater fish are constant flow of water from the environment into the cells
Based on these observations, in what type of environment must these fish live

parasites can detrimentally affect their host, but also must not allow their host to die before they can complete their life cycle. some parasites have complex life cycles with many different hosts, and have had to find ways of persisting in many different environments during the change from one host to another. ectoparasites live outside the body of the host, and can more easily  disperse, but are  more exposed to predators, parasites, parasitoids. endoparasites live inside the body of the host, and are therefore protected from the outside environment. but they can be  attacked by the host's immune system. they have therefore developed  mechanisms for dispersal such as  complex life cycles.

pregnancy happens more and more

i believe your answer would be c.. : )

the answer is true when observing or determining population size, a direct observation is use, in which each organism is counted in a population or in an area. one benefit of this measure is that you get the exact population count but it will take a long time to  determine  the  size  of a  population.