Determine whether POSITIVE feedback mechanism or NEGATIVE feedback mechanism


1. If the blood sugar level drop, the brain sends signals to the pancreas to release glucagon that instructs the liver to convert glycogen into glucose to return blood sugar into normal level.
2. When you are cold, the blood vessels constrict and the body shivers to increase body temperature.
3. The injured blood vessels in a bleeding wound releases substance to start blood clotting.
4. The oxytocin released in the uterus during labor results to the contraction of uterus. The contractions stimulate the release of more oxytocin which results to stronger contractions.
5. The hypothalamus produces gonadotropin-releasing hormone (GnRH). The GnRH signals the pituitary to produce follicle-stimulating hormone (FSH) which stimulates the ovaries to produce estrogen. High levels of estrogen prevent the production of GnRH and causes the pituitary to make less FSH.
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