You take a vacation to Denver, Colorado. The elevation of Denver is 5,280 feet above sea level. Rochester NY is only 505 feet above seal level. Within a day, you're feeling pretty tired and have a general lack of energy. However, by the end of your vacation, you're feeling much better. Why is an acclimation period to high altitude necessary? Using your vacation scenario, identify the following components of the red blood cell production homeostatic control loop. Please provide your answers in a list with numbers (1-6) so that your answers are clear.
What is the "controlled variable" in this homeostatic feedback loop (what is actually being 'measured')?
What or where is the "sensor" (where are the cells that are doing the 'measuring')?
This sensor will send a message to the "control center". Where or what is the "control center" (the 'control center' is the organ or structure of the body that is going to respond to deal with the information measured)?
What signal does the control center send to the "effector" (what place in the body is going to respond to fix the problem)?
Where is the "effector"?
What is the ultimate "goal" of this feedback loop?
Full Answer Section
Components of the red blood cell production homeostatic control loop in your vacation scenario:
- Controlled variable: The controlled variable is the amount of oxygen in the blood.
- Sensor: The sensor is the chemoreceptors in the carotid bodies and aortic bodies. These chemoreceptors are sensitive to changes in the oxygen levels in the blood.
- Control center: The control center is the kidneys.
- Effector: The effector is the bone marrow.
- Response: When the chemoreceptors detect a decrease in the oxygen levels in the blood, they send a message to the kidneys. The kidneys then produce erythropoietin (EPO), a hormone that stimulates the production of red blood cells in the bone marrow.
- Feedback: As the number of red blood cells increases, the oxygen levels in the blood increase. This feedback loop ensures that the oxygen levels in the blood are maintained within a normal range.
List of components of the red blood cell production homeostatic control loop:
- Controlled variable: Amount of oxygen in the blood
- Sensor: Chemoreceptors in the carotid bodies and aortic bodies
- Control center: Kidneys
- Effector: Bone marrow
- Response: Production of red blood cells in the bone marrow
- Feedback: Increased oxygen levels in the blood
Example of how the red blood cell production homeostatic control loop works in your vacation scenario:
When you first arrive in Denver, the air pressure is lower and there is less oxygen in the air. This causes your oxygen levels to drop. The chemoreceptors in your carotid bodies and aortic bodies detect the drop in oxygen levels and send a message to your kidneys. Your kidneys then produce erythropoietin (EPO), a hormone that stimulates the production of red blood cells in your bone marrow.
Over time, your bone marrow produces more red blood cells and your oxygen levels increase. Once your oxygen levels return to normal, the production of EPO stops.
By the end of your vacation, your body has acclimated to the high altitude and you are no longer feeling fatigued or short of breath.
Conclusion
The red blood cell production homeostatic control loop is a complex system that ensures that the oxygen levels in the blood are maintained within a normal range. When the body is exposed to a new environment, such as a high altitude, the homeostatic control loop is activated to adjust the body's physiology to the new conditions.
Sample Answer
An acclimation period to high altitude is necessary because the body needs time to adjust to the lower oxygen levels at high altitudes. At high altitudes, the air pressure is lower, which means that there is less oxygen in the air. This can cause a number of symptoms, including fatigue, shortness of breath, headache, and dizziness.
The body acclimates to high altitude by increasing the number of red blood cells and by producing more hemoglobin. Red blood cells carry oxygen, and hemoglobin is the protein in red blood cells that binds to oxygen. By increasing the number of red blood cells and the amount of hemoglobin, the body is able to deliver more oxygen to the tissues.