The ability of an animal to maintain a stable internal environment is called homeostasis
Answer;
-Sympathetic nervous system
After cheering wildly at an exciting football game your body may begin to relax on the way home. This relaxation reflects activity of the sympathetic nervous system.
Explanation;
The sympathetic nervous system is part of the autonomic nervous system, which also includes the parasympathetic nervous system.
The sympathetic nervous system activates what is often termed the fight or flight response. Like other parts of the nervous system, the sympathetic nervous system operates through a series of interconnected neurons. Sympathetic neurons are frequently considered part of the peripheral nervous system (PNS), although there are many that lie within the central nervous system
Your answer will probably be A compound microscope speaking how compounds are pretty small.
The organic compound is LIPIDS.
Cholesterol is one example of lipids.
Lipids are a diverse group of organic compounds, which inclused fats, oils, hormones, waxes, certain vitamins and some membrane components. They do not dissolve in water. Lipids are found in the living cells and they make up the building blocks for the structure and functions of living cells.
Answer: C. The sign of the enthalpy of the reaction reverses.
Explanation: Enthalpy of a reaction is the net heat absorbed or released during a chemical reaction.It is represented by 
. It is negative for exothermic reactions in which heat is released and is positive for endothermic reactions in which heat is absorbed.
When a chemical reaction is reversed the heat of the reaction changes its sign.
The decomposition of calcium carbonate is an endothermic reaction as heat is required to break the bonds and thus energy is absorbed.
When the reaction is reversed, the reaction becomes exothermic as now bonds are getting formed and energy is released.
