Give other examples of disturbances in the internal environment that can act as a stimulus to a feedback mechanism.
Isolation is not the home court of the body. A trove of bodily businesses are required to achieve homeostasis. And in the process, it is inevitable that there are disturbances that may befall. Few of the examples below indicate disruptions in the internal environment that can act as a stimulus to a feedback system.
A. Positive Feedback System
Blood clotting
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Every time a tissue is injured, especially when it is in the form of a wound, chemicals are expelled. Multiple activations of clotting factors are demanded for blood to change from a liquid to solid state. Fibrin clot develops as soon as one clotting factor is activated. This then triggers the activation of the following clotting factor to accomplish such a task. Owing to this ground, stimulus's orientation is maintained during this procedure.
Menstruation
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At the rear of a menstruation’s existence, estrogen is released by the ovary. When estrogen reaches the brain, both the pituitary gland and hypothalamus govern in manufacturing luteinizing hormones and gonadotropin-releasing hormones, correspondingly. More estrogen is emitted from the ovary as a result of LH, and this positive feedback loop raises blood levels of GnRH and LH. With follicle-stimulating hormone (FSH) brought into play, these hormones rise, paving the way for ovulation to commence.
Digestion
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Intake of food requires digestion. To bring the aforementioned process into its fruition, an inactive version of an enzyme is discharged called pepsinogen. Exuding an exceptional degree of confidence in reifying homeostasis, pepsinogen is converted into pepsin, which is responsible for polarizing proteins into smaller peptides. Modification of the substance sets off a positive feedback loop that translates additional pepsinogen molecules in the stomach to pepsin, building up enough pepsin in the stomach to allow for protein digestion.
B. Negative Feedback System
Osmoregulation
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Fluids are scattered around at various landmarks within the body to perform specific functions and osmoregulation is the commander of its appropriate concentration. The occurrence of this process is very evident when the body is dehydrated, ADH is secreted to help retain water, and its release is suppressed when the body is hydrated. Specific vascular receptors are activated by extracellular dehydration, which tells the brain to start drinking and release ADH. Thus, striking the balance at a cellular level.
Calcium Homeostasis
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Negative feedback system can be observed in the scheme of calcium homeostasis. Sensory organs that respond to calcium ion concentrations include the main cells in the parathyroid glands and the parafollicular cells in the thyroid glands. The main cells are stimulated to secrete parathyroid hormone by a decrease in plasma calcium ions, whereas the parafollicular cells are stimulated to do the opposite by an increase in plasma calcium ions.
Thermoregulation
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Hypothalamus in the brain is in-charge of regulating the body temperature. When the hypothalamus senses that the body is getting too warm, the body starts to perspire in an effort to bring the temperature down to a healthy range.