Chemicals: Tiny Blocks of Life
Chemicals are some of the tiniest blocks in the "Pyramid of Life". Atoms held together by electron clouds form these chemicals. Often these bonds form ordered patterns such as triangles, cubes, and hexagons. Water is shaped like a V with the Oxygen atom holding two hydrogens to it. This is a covalent bond - where electrons are shared.
Ionic bonds are formed by one atom giving up electrons to another atom. An example of this is common table salt where sodium and chlorine come together because chlorine is stealing one of sodium's electrons. This lack of an electron on the part of sodium gives it a positive charge, and the extra electron on the Chlorine atom gives it a net negative charge. (Remember that all electrons are negatively charged.)
Organic compounds must have some carbon atoms. Carbon atoms can also bind with themselves, so they can create very long chains. DNA is made up of log chains of carbon molecules. Carbon molecules tend to be fairly stable.
Generally, chemicals which are alike in their electrical charge and bonding tend to mix well, or dissolve into one another when they come in contact. When a solute (a thing to be dissolved) is mixed with a solvent (a dissolver) the result is a solution. In the body a common solvent is Sodium Chloride (NaCl). Sodium mixed with water then results in a saltwater solution. Sodium is an electrolyte because it breaks down into ions when it is mixed with water.
Just as carbon can form chains, it can also form closed rings and branching trees. It uses these structures to create the four main body-builders: proteins, lipids, carbohydrates, and nucleic acid.
Some chains contain nitrogen and hydrogen in the form of amino acids. These form a structural protein which turns out to be a basic building block contained in most animal and plant tissues. Enzymes are another form of protein. It functions to speed up chemical processes within the cells.
Fats are also known as lipids. These are carbon chains linked with hydrogen and oxygen that tend not to be dissolved in water (so water is not a solvent for lipids). Lipids are created in many animals when excess food is consumed. It stores the energy for future use. In developed countries these lipids are seldom called upon to be turned back into energy, and the continuous build up of excess lipids can create a problem for humans and domestic animals. Hormones are also a form of lipid.
A chain of carbon and water can form into carbohydrates. One carbohydrate is glucose, it is a closed ring molecule. Glucose and other carbohydrates are a sugar that is used within the cell to convert to energy.
In the nucleus of eukaryotic cells nucleic acid can be found. it is a carbon chain containing nitrogen as a base. There are two kinds of nucleic acid, DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). DNA comes in the form of a double helix and they serve as a code for the creation of certain proteins and other chemicals. RNA makes copies of these codes.