Biochemistry CH. 6

Atoms, Elements, and Compounds Atoms : building blocks of all matter Structure: P+, N, e- Elements are made of only 1 type of atom Cannot be made any smaller 92 natural ones (100 known) Periodic Table of Elements: Vertical Rows= Groups (Similar) Horizontal Rows= Periods

Isotopes: Elements always have the same # of protons However, can vary on neutron number (Isotope) Ex.) C-12 & C-14 Radioactive isotopes give off radiation do to the nucleus breaking down Used to radio-carbon dating (1/2 life) Very accurate

Compounds and Bonds…James Bond Formed when 2 or more elements combine Ex.) H2O Different than the elements they came from Cannot be broken down into simpler elements by physical means Bonds: 2 types Covalent: electrons are shared Ex.) Water These create molecules Ionic: electrical charged attraction Ex.) NaCl

Chemical Reactants: When elements or compounds are changed into something else Reactants go on left side  products on the right side All reactions require energy: Minimal amount of energy needed for a reaction (activation energy) Enzymes: catalysts that lower the activation energy in the human body Specialized proteins with specific lock-key model Lock is enzyme, key is substrate

Water… It is essential for life Much of its biological functions come from its structure However water is very unique and complicated…it has issues It has what we call “ polarity ” Mickey Mouse compound This is why it is a universal solvent Like dissolves like

Mixtures Combination of 2 or more substances Nothing really changes 2 types: Homogenous (solution): everything uniform and can’t tell it apart Solute is dissolved in solvent Heterogeneous: remain individual traits Ex.) Blood, milk, muddy water

Acids and Bases: Acids: pH lower than 7 (release H+) Base: pH higher than 7 (release OH-) pH and Buffers: Most processes of the cell occur at 6.5 and 7.5 pH Antacids are used as a buffer (something that play with the acidity levels of foods or beverages)

Organic Chemistry: Carbon Compounds Carbon makes up almost all biological molecules Carbon atoms have 4 e - in its outermost energy level 8 outer electrons make an element stable so Carbon forms with other elements to stabilize itself This leads to enormous variety in Organic Chemistry -single bonds, double bonds, and triple bonds

Large Carbon Molecules Many molecules are built from smaller molecules -these are known as monomers Monomers can bond to one another and form complex molecules -these are known as polymers Large polymers linked together are Macromolecules

Molecules of Life 4 main classes of organic compounds are essential for life processes to work 1.) Proteins 2.) Carbohydrates 3.) Lipids 4.) Nucleic Acids Even though all made of the same atoms (O, N, C, H) they all have different properties and characteristics

1.) Carbohydrates… Carbohydrates exist as monosaccharide's, disaccharides, and polysaccharides Monosaccharide: is a monomer of carbohydrates -Examples: glucose (simple sugar) Now when 3 or more sugars combine they form a polysaccharide -ex.) Glycogen: animals store it liver and muscles -ex.) Starch: plants store this in the cell as either cellulose which builds cell walls or as storage vessels in the plant itself

2.) Proteins: Almost all of life’s processes use proteins (15% of body mass) Organic compounds made of monomers just like carbohydrates -Amino acids are the building blocks of proteins (20) When amino acids bond (peptide bond) to each other and form a very long chain it is called a polypeptide These chains create proteins when they fold

3.) Lipids & 4.) Nucleic Acids: Lipids: Fats, oils, waxes Store energy Can be saturated (bad) or unsaturated (good) with hydrogen (makes it easier to spread) Ex.) Butter vs. Fat Steroids: cholesterol & hormones (good and bad) Nucleic Acids: store and transmit genetic information Made up of nucleotides (A, C, T, G, U) 2 types : DNA and RNA