Biology

BIOLOGY 3

Chemicalreactions taking place through various activities such recyclingshows the re-arrangement of atoms within a substance. Ideally, atomshold materials together even after being subjected through processessuch as heating. There exist electron cells within atoms andmolecules. The interaction between the atoms within a substance ismade possible by the existence f chemical bonding. Chemical bondshelp in maintaining the stability of an atom. Different substanceshave different number of electrons hence differences incharacteristics. In their different forms such as liquid and solid,substances reflect distinct arrangement of the electrons. It is aknown fact that the number of electrons in the outermost electronicshell determines the energy levels and reaction intensity of asubstance. Substances with atoms whose outer shells are not filledhave a possibility of reacting with other atoms.

Inorder to attain stability, atoms have to fill their outer electronicshell. This is realized through accepting electrons, giving awayelectrons or sharing electrons with the bonding atom. The process islargely dependent on the number of electrons in the outer shell. Thisresults in the formation of a new substance. Sometimes, energy isreleased when either of the process takes place. The newconfiguration of atoms is a reflection of the chemical processes thattake place in changing a substance from one to another. Synthesis ofplastics, for instance, is an indication of new configuration ofelectrons. There exist three chemical bonds namely covalent, metallicand ionic bonds. These bonds ascertain the evidence on redistributionof electrons. The process also gives rise to three forms chemicalattractions namely polarization, van der Waals and hydrogen bonding.The bonds highlighted above match to a given form of attraction.Ionic bonds arise from electrical energy that occurs betweenpositively charged ions. The reaction between sodium and chlorine isa god example of ionic bonding. The arising from the bondage areusually strong. Metallic bonds occur due to the transfer of electronsbetween atoms. The electrons are then redistributed within the commonshell that binds the atoms. Sodium atom, for instance, may lose anelectron to achieve a stable 10-electrons configuration. The extraelectron forms a cloud of negative charge in metals. Most of thechemical elements are known to occur in metallic state. On covalentbonds exist in bonded molecules from the same element. Hydrogen andnitrogen molecules, for instance, undergo covalently-bonded.

Anumber of interactions take place when the substrate molecule isbinding with the active site. Electrostatic interactions, hydrogenbonding and hydrophobic are some of the interactions that take place.In hydrophobic interactions, for instance, protein molecules repelwater molecules. Another important process to consider ispolarization that is reflected in elements that have both positiveand negative ends. Forces due to polarization enable substances todissolve in water. Water is known to have strong polar molecules.Hydrogen bond exists due to the process of polarization. The bond iscommon in almost all the biological substances. It links the DNAmolecules in the body of a living organism. Organic molecules may endforming lipids that do not dissolve in water. Some of the lipidsubstances include fats and wax. The existence of carbon in thesemolecules makes it difficult to dissolve in water. The lipidstructure has four bonds which combine with hydrogen to formsaturated or unsaturated fats depending on the number of bondingcarbon atoms. Other elements that do not have hydrogen, nitrogen,oxygen or carbon are classified as vitamins and minerals.