Final answer:
Complex organisms maintain internal balance through negative and positive feedback systems, which regulate physiological processes such as blood glucose levels and childbirth, respectively.
Step-by-step explanation:
Complex organisms rely on feedback mechanisms to maintain their internal environments and respond to changes in external environments (2.C.1). These mechanisms help regulate growth, reproduction, and ensure dynamic homeostasis. Two primary types of feedback systems are negative feedback and positive feedback.
Negative Feedback
Negative feedback mechanisms work to correct a deviation from a set point, and tend to stabilize physiological variables. An example of this is the regulation of blood glucose levels. When glucose levels rise, the pancreas secretes insulin, causing cells to uptake glucose and decrease blood glucose levels. Once levels return to normal, insulin secretion decreases, stabilizing the glucose concentration.
Positive Feedback
In contrast, positive feedback mechanisms amplify the initial stimulus. A classic example is the process of childbirth. During labor, the release of oxytocin causes contractions, which then intensify the signals for more oxytocin and contractions, until the baby is born and the stimulus stops.
These feedback loops ensure that organisms can justify claims with evidence and justify a claim made about the effects on a biological system (6.1, 2.15). For instance, if one were to alter a component within the negative regulatory system of blood glucose, such as insulin, various physiological or organism level changes would occur due to the disruption of homeostasis.