Fast heart rate: Tachycardia means fast heart beat. Sinus node is the structure where normally heart rhythm and beat is originated, and it naturally responds to stimuli when the heart needs to beat faster. Inappropriate sinus tachycardia is when the heart is beating fast, when it shouldn't. ...Read more.
An atom is the smallest unit of an element that retains the identity (and the chemical properties) of that element. + 66 others found this useful. Sandra Pinzon.Edit.he atom is the smallest particle of an element that retains it's characteristics. Sub-atomic particles such as protons, neutrons and electrons form the atom and it is the amo â¦ unt of each of these sub-atomic particles that make the element that element. 5 people found this useful.
This happens via a chemical reaction. A molecule is the smallest amount of a chemical substance that can exist. Essentially, a compound is a type of molecule. A molecule can be made up of two or more atoms of the same element or two or more atoms of different elements. However, compounds are molecules that are made up of atoms of different molecule. Atoms are the basic units that all matter is made of. Atoms are tiny, ranging from 0.1 to 0.5 nanometers in width.