ick either a positive or negative feedback loop that can be seen involving this organ. Explain the stimulus, sensor, integrator, and effector specific to this feedback loop.

Question

I need this for bio and when it said the organ- it is the nervous system so yea!

Answer 1

Hello,

Let's first break down what the question is asking. When thinking of any feedback loop in biology, you first need to have a vision of what the loop looks like.

In the case of a negative feedback loop, you can imagine a thermostat, like the one that controls your AC at home. The thermostat is the integrator; it gathers all of the data to determine if the system has reached its objective. The thermostat itself contains a thermometer which is the sensor, as is mentioned in the question. It's job is to determine where the system is in regards to its mission, in this case keeping a set temperature. The stimulus in this case is the deviation in temperature from the set point. The AC unit is the effector; its job is to push air around in order to reach the proper temperature and it does so simply by turning on or off on command from the thermostat.

An example of this system at work: You set the thermostat in your home to 75 degrees on an 80 degree day. The thermometer (sensor) reads out to the thermostat (integrator) that it is 80 degrees (stimulus) and the thermostat in turn tells the cooling unit (effector) to turn on. As the cooling unit works the temperature in the room reaches 75 degrees (new stimulus) and the thermostat integrates that information to then tell the cooling unit to shut off (negative feedback).

The nervous system also works on feedback loops as in the previous example. A great example of this is kinesthetics. In the muscles and tendons are sensors (Golgi tendon bodies and muscle spindle fibers) which serve the same role as our thermometer in the above examples. They report information to the brain about where our limbs are and what force they are using (stimulus). If your goal is to life a 10lb object, your muscles are directed by the cortex of your brain to apply a certain amount of force (the effector). The Golgi tendon bodies and muscle spindle fibers record the movement of your muscles to determine if the force was sufficient to move the object. If the object did not move sufficiently, they send that information back to the cortex (integrator) which then directs the muscle to apply more force. This feedback loop continues until the sensors report back to the cortex that the force applied moved the object the desired amount at which point the cortex orders the halting of more force being applied. If too much force is applied and the object moves too much, a negative feedback loop is triggered and the cortex orders less force.

If you can simply imagine the feedback loop in this way, you can understand how the nervous system is able to account for and measure movement in space. And going forward, understanding feedback loops in this way, always searching for what element in the system plays each role from the thermostat example, you can solve any feedback problem no matter which system of the body is in play.

I hope this helps and feel free to reach out to set up a session with me if you have any further questions.

Best of luck!

Brandon Berman