What are density-dependent factors? any examples?

The nursing instructor has been observing nursing students initiate an iv infusion. which action(s), if made by the nursing student, indicates that further instruction is needed? (select all that apply.) the nursing student:

An ecologist studied the same species of deer during the summer and the winter. she noticed that during the summer, when there was plenty of food, the deer were energetic and playful. however, during winter when food was scarce, the deer moved more slowly and did not run unless they needed to escape a predator. which scientific fact is best supported by her observations?

Which process in respiration happens first? a)pyruvate processing b)electron transport chain c)krebs cycle d)glycolysis