Chapter 2, Problem 1TYC

To determine

To explain: The most common type of feedback loop in nature and the feedback loop that results because of the actions of humans and examples of both the types of feedback loop.

Answer to Problem 1TYC

In nature, the negative feedback loop is more common than the positive feedback. The feedback loop which results from the human activity is positive feedback. The example of negative feedback is the regulation of blood pressure and the example of positive feedback is the childbirth.

Explanation of Solution

A system on Earth can be defined as the interaction of the parts, components, and elements through the exchange of the matter, information or energy. The feedback loop can be defined as the process in which the output of the system becomes input of the same system.

There are two different types of feedback loops, namely the positive feedback and the negative feedback. In the negative feedback, the system moving in a certain direction leads to the generation of an output which moves the system in opposite direction. This kind of feedback loop stabilizes the system. It is more commonly found in nature.

In the positive feedback, the output of the system drives the direction of the system toward the extreme. Increased output in the positive feedback leads to an increase in the input. This kind of feedback leads to the movement of system away from equilibrium. The negative feedback results from the actions of humans.

One of the examples of negative feedback loop can be the regulation of human blood pressure. In case, when the blood pressure of body increases, the signals of high blood pressure are sent to the brain from the vessels. From the brain, these signals are sent to heart which decreases the heart rate, thereby reducing the blood pressure to normal.

The example of the positive feedback loop is the childbirth. The fetus in the uterus put pressure on cervix, which results in beginning of contraction. Oxytocin is released when more pressure is put on cervix. This causes more contraction. With an increase in the contraction, more pressure is put on cervix and pressure is increased. This is positive feedback regulation.