General Science Questions

PTH - Parathyroid hormone which balances calcium levels if they are low.

The nervous system is the part of an animal that coordinates its actions by transmitting signals to and from different parts of its body.

In vertebrates it consists of two main parts, the central nervous system (CNS) and the peripheral nervous system (PNS). The CNS consists of the brain and spinal cord. The PNS consists mainly of nerves, which are enclosed bundles of the long fibers or axons, that connect the CNS to every other part of the body.

The nervous system has three main functions:

* To collect sensory input from the body and external environment.

* To process and interpret the sensory input.

* To respond appropriately to the sensory input.

Iron reacts with oxygen in the presence of moisture or water to form a red oxide called rust and the reaction involved is called as Redox reaction.

The air around us is a mixture of gases, mainly nitrogen and oxygen, but containing much smaller amounts of water and other gases.

Earth's atmosphere is composed of many gases. Their percentages by volume is given by::

 
78% Nitrogen,

21% Oxygen,

0.9% Argon, and

0.03% Carbon dioxide 

And very small percentages of other elements.

The three main functions of Kidneys are ::

* Regulating and filtering minerals from blood.

* Maintaining overall fluid balance.

* Filtering waste materials from food, medications, and toxic substances.