<span>A biologist can infer from a population that is uniformly distributed through its habitat that it has reached it's carrying capacity. If resources were unevenly distributed through the environment, you would not see a uniform distribution of the population itself.</span>
Answer:
Its D, The cell membrane(also known a the plasma membrane) has a job in which it has to allow passage in and out of the cell. Therefore it can prevent harmful substances from entering the cell. Think of it as security, either allowing you access or denying you depending on if you're a threat
Pathogens can exist in blood and then can be passed the transfusions
Mutualism since the clown fish and the anemone both benefit from each other.