Biochemistry Review

Biology is the study of living things. Organic or Biochemistry is the study of the

chemical reactions in living things.

What is the smallest unit of matter? An Atom

Atoms- What area is positive and what area is negative? The nucleus is positive The electron cloud is negative

Where is the mass? In the nucleus

Atoms

Atomic Number= # of protons Atomic Mass= P+N First Energy Level= can hold .. 2 electrons Second Energy level can hold.. 8 Electrons

What is a molecule?

A group of the same kind of atom held together with covalent bonds

How are ions and isotopes same/different? They are both molecules and the number of

protons stays the same, BUT

Ions have different charges (different number of electrons)

Isotopes have different masses (different number of neutrons)

What makes a molecule polar? Uneven sharing of electrons gives the

molecule partially negative areas and partially positive areas

Give an example of a polar molecule.

Water – H20=Oxygen has a negative charge, hydrogen has a positive charge.

What is a compound?

A substance made of two or more different elements.

These elements are held together with ionic bonds.

What is the most common element in living things? Carbon It is present in all four of the

biomolecules Which biomolecule contains

nitrogen? Protein

Let’s talk about bonds!

What are the three types we have covered? Ionic, Covalent, and Hydrogen bonds

A Bond formed when molecules share electrons

Covalent Bonds

A Bond between two oppositely charged molecules (one positive one negative) Ionic bonds

A Weak bond between polar molecules

A Hydrogen Bond

Four Categories of Biomolecules Proteins Carbohydrates Lipids Nucleic Acids

These are very large molecules so we call them Macromolecules!

Carbohydrates- What do we know? Ratio of C:H:O is 1:2:1 Monomers are: saccharides-simple sugars Polymers are: polysaccharides- starches

Lipids

Monomers are glycerol and fatty acids Polymers are Trigycerides- a glycerol with

three fatty acid chains Lipids can be fats or oils, They are nonpolar- don’t mix with water Saturated fats are solid (butter, lard) Unsaturated are oils (olive, vegetable)

Proteins

Monomer is an amino acid (20 types), each amino acid has an R group on its central carbon.

Polymers are polypeptides, two or more amino acids bonded together

What is the process that builds polymers from monomers? Dehydration Synthesis (synthesize is to

make) Remember this process gives off a molecule

of …… H20

Breaking down polymers into monomers is called Hydrolysis- “Lysis” is to break

What molecule is needed for this to happen? H20 must be present and breaks into its parts

to replace the H’s and O

pH scale 1-14

What does it measure? The acidity or basicity of a solution 7 is neutral Acids are … Below 7 Bases are … Above 7

This is the end.Best of Luck!