A gateway substance is something that may be menial but could lead to something bigger, an example is weed in the drugs world, weed is not hard to get and is usually a gateway drug to stronger types of drugs and potentially more dangerous
Answer:
See the answer below
Explanation:
Homeostasis refers to the maintenance of relatively constant internal body processes. This is done in two ways
- <em>Negative feedbacks</em>
- <em>Positive feedbacks</em>
Negative feedback returns body processes back to normal after the process has been breached. An example is when the body temperature becomes too high or too low. At too high temperature, vasodilation of the skin's blood vessels occurs and more heat is lost to the surrounding from the skin, sweat is also produced by sweat glands and evaporation of the seat causes cooling. At too low temperature, vasoconstriction occurs leading to the conservation of more heat. The muscles also shake to generate more body heat
Positive feedback ensures that a breach of body processes reaches completion. An example is when a pregnant woman starts laboring. The increase in the amount of oxytocin in the blood leads to the contraction of the uterus consequently leading to the opening of the cervix. More and more oxytocin leads to more frequent and stronger contraction of the uterus untill the baby is born.
The answer is: [D]: "ammonia" .
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It was from darwin he was the 1
