Welcome to My AP Biology Thoughts podcast, my name is CJ and I am your host for episode 92 called Unit 4 Cell Communication and Cell Cycle: Feedback loops. Today we will be discussing how organisms maintain homeostasis

•  There are 2 types of feedback loops found in the systems of our bodies. The first is negative and the second is positive. These feedback loops are ways for our body to determine whether the cells are healthy or sickly. These feedback loops typically occur when the product or output of an event or reaction changes the organism's response to that reaction. So typically, the cells in our body do not want anything to change, they have to have optimal temperature, pH, concentration, everything. The process of regulating these happen during feedback loops and different stimuli and reactions occur to perform this. Looking at the different types of feedback loops, we can see that both try to maintain homeostasis. They both have an overarching goal of consistency and equilibrium. 

•  Negative feedback loops are typically the most popular and common example of feedback loops. This is when a stimulus disrupts a receptor. This receptor then in turn puts out various tasks to help alleviate the stimulus until it is all gone. A great example of this is the thermostat in a house. The stimulus is the temperature getting too cold. This negative feedback in turn activates the thermostat which turns on the heat. And until the temperature in the room matches the temperature on the thermostat, the heat continues to warm up the room. Now for the opposite; a positive feedback loop. This is just a series of different reactions that cycles until a big event occurs at the end of it. The best way to look at these different types of feedback loops is to look at the graphs that represent them. On the X-axis is time while the y-axis is stimulus. The cell wants to be at 0, which means homeostasis. Now for negative feedback loops, we see that the line starts at 0 but then an event occurs that throws off the balance. Either going up or down, the cell corrects it and heads towards 0, however it overshoots and continues the pattern of a sine graph until its amplitude slowly reaches 0. Positive feedback loops are a bit different. In terms that the graph slowly goes up and up until it reaches the even and then plummets back to 0. These graphs help us visualize the process and the final goal of each loop.

•  This all plays into the theme of systems in biology. Systems in our bodies run all around the clock to maintain homeostasis and to keep us healthy and strong. These feedback loops are necessary to tell the cell whether something is wrong or right, and this is what causes these loops. It is important to know this because these types of activities ties into everyday things. Just like thermostats and pregnancies. It is important to know and understand these things so we know when something goes wrong. It’s also important to note that our bodies are functioning the right way and it’s constant need to keep us healthy.

Thank you for listening to this episode of My AP Biology