Negative Feedback Loops

Negative Feedback Loops happen when the output of a system turn out opposite to the input of the system. If the feedback is negative, then the system is stable.

An example of a negative feedback loop are blood sugar levels that have to be regulated in order to keep the human body in homeostasis. Neurones in the hypothalamus in the brain detects glucose and increases or decreases insulin accordingly. Insulin is what changes glucose to glycogen.

This graph of blood sugar levels shows a negative feedback. The reversed u shape of the graph shows how with the intake of sugar and the output of insulin happens within the body to re achieve homeostasis.

sdfsd
Yo u can see the negative feedback loop in this graph. The graph displays how Dr. Roods Blood sugar reacted after consuming a candy bar and a soda. You can tell by the upside down U shape of the graph that while the sugar first made it go up the change was then leveled by the insulin response. Through this process the body is able to reach homeostasis.

Lab #4

Dirt & Soil & Community Gardens

This lab concerned community gardens. There is one at Mercer right across from the MEP parking lot. It had various flowers and vegetables growing in it: okra, lima beans, eggplants, and various other herbs. At home, we grow tomatoes every year at the top of our yard.

One of the concerns about soil and the reason to test it regularly is because old houses in the area were painted with lead paint. In order to make sure it isn't contaminating the gardens soil testing is necessary! One thing to help is to plant in boxes with retaining walls.

Another part of the lab was learning about different types of soil. It is easy to test it by feeling how a small mud fall reacts. Here is a chart to help distinguish types of soil.




There are 12 soil orders of the world.
Entisol, Aridisol, Alfisol, Ultisol, Gelisol, Andisol, Inceptisol, Mollisol, Spodosol, Oxisol, Histosol, Vertisol.

Georgia's most common soil type is Ultisol. It is more commonly known as red clay. This soil type is most commonly found in the southeastern United States.


Utisol, or red clay