All of the systems that are aroused by the <span>sympathetic nervous system</span> are relaxed by the parasympathetic nervous system.
<span>autonomic nervous system (ANS) is a part of the central nervous system that controls all parts that the human cannot have a control on (which are done automatically) like heart rate and breath
ANS is divided in two opposite systems: sympathetic and parasympathetic:
</span>Parasympathetic nervous system: caracterized by the tag "<span>rest and digest" it decreases the heart rate, blood pressure, and breath. It increases the gastrointestinal motricity, letting the organism resting (this happen after a meal).
</span>Sympathetic nervous system: caracterized by the tag "fight or flight" it increases the heart rate, blood pressure, and breath. It decreases the gastrointestinal motricity, letting the organism focus on its environment (this happen when we are in danger).
Natural Selection is when traits are "naturally" selected for, because "survival of the fitttest." Example would be a species becoming bigger over time, because the smaller animals of that species were more likely to be eaten by predators. Natural selection is when the "best" trats are passed down due to chance
Selective breeding is if an outside forece (like a dog breeder) "chooses" a triat to be passed down. Example, instead of breeding a brown dog with a white dog, the breeder breeds two black dogs together in orer for the litter to all have black fur
Tropism
It is a biological phenomenon, indicating growth or turning movement of a biological organism. This is usually a plant in response to the environmental stimulus. This response is dependent on the direction of the stimulus. The stimulus must be perceived first, followed by movement towards or away to the stimulus. There are various types of tropism which are chemotropism, exotropism, geotropism and electrotropism.
The answer is Habitat. I'm 100% sure it is.
Answer:
silicon and carbon have tge same number of valence electrons !
