Molecular Biology Inorganic Chemistry

Biochemistry means LIFE..!! The Atom : is the basic unit of matter Is composed of many small particles

The Atom .. Inside the Nucleus there are TWO particles The Proton (positive) The Neutron (neutral) .. Outside of the nucleus, roams the Electron (negative)

The Nucleus of the Atom The Nucleus Is the inner part of the atom Has an overall neutral charge due to the protons within

Atoms … Each atom of the periodic table is unique. And, until atoms react with another, they are: Neutral # of Protons = # of electrons

The Periodic Table

Using the Periodic Table Proton number Element’s Symbol Atomic Mass

Electrons .. Electrons exist outside of the nucleus, are extremely small and so are nearly weightless. Electrons control all the action of the atom

Let’s draw some atoms…

Covalent Bonds… Let’s bond two hydrogen and one oxygen to make water! We just created a covalent bond. This is a bond in which one or more atoms share electrons so that they all become more stable (happy).

Ionic Bond .. Some atoms do not want to share electrons; they actually take the electrons from another atom. The stronger atom GAINS electrons, which are negative, so the atoms become a NEGATIVELY charged ION or Anion What is an ion? An Atom with a + or – charge.

Ionic Bond The weaker atom, which LOSES electrons, becomes a POSITIVELY CHARGED ION or a Cation.

https://www.youtube.com/watch?v=zpaHPXVR8WU Ionic bond Once these atoms become IONS, they are now attracted to one another = IONIC bond

Ionic Bond Sodium atom ion Chlorine atom ion

Covalent or ionic bond? How do we know which one will form?? two Nonmetals will form a covalent bond Right side of stair step A Metal and Nonmetal will form an ionic bond From opposite sides

The Periodic Table

Venn Diagram Identify 2 similarities and 2 differences with IIONIC and Covalent bonds…!

Water: Why it is important! Cells cannot LIVE without water. Water is present in and around of all cells. Water shapes the cell membrane. Water is involved in the making and breaking of molecules in our bodies. Organic chemistry

Water … Water’s chemical formula is H2O Water is polar ! This means that one side of the molecule is partially positive (+) and the other side is partially negative (-). This happens because one atom wants the shared electrons more than the other atom. TUG-OF-WAR

Water … Which atom has the greater power ? Oxygen !!! Hydrogen Ends up with a partial NEGATIVE charge ! Hydrogen Ends up with a partial POSITIVE charge. Opposites charges ATTRACT.

Opposite charges Attract.. Because a water molecule is polar, it is attracted to other water molecules This is called Hydrogen bonding This attraction between water molecules creates .. Tension = known as intermolecular forces

Opposite charges Attract.. Water also has an attraction for other polar molecules, like glass and ionic compounds. When water is attracted to another polar substance it is called: Polarity

So, Why is polarity important? It helps give the cell membrane its shape It allows water to “stay together” It allows water to dissolve and be attracted to a lot of substances Especially in your blood stream and cells It allows the formation of the hydrogen bond, which holds your DNA molecule together in the middle