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Biochemistry. Review. Atoms- the building blocks of matter Nucleus- the center of an atom Proton-positively charged particle in the nucleus Neutron-neutral particle in the nucleus of the atom Electron- negatively charged particle outside the nucleus. More Review.
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Review • Atoms- the building blocks of matter • Nucleus- the center of an atom • Proton-positively charged particle in the nucleus • Neutron-neutral particle in the nucleus of the atom • Electron- negatively charged particle outside the nucleus
More Review • There are many chemical Rxn’s taking place in your body • Chemical reactions are when atoms or groups of atoms reorganize • Bonds are broken and reformed during the process
Ugh… More review • An element is a pure substance that can’t be broken down into another substance • All known elements are located on the periodic table • Isotopes- same number of protons different number of neutrons • May be radioactive • Carbon 12 v. Carbon 14
Still reviewing….. • Compounds- one or more elements combining to form a new substance • Always found in certain ratios (H2O) • Chemically and physically different from the elements it consists of (H or O goes boom) • Can’t be broken into simpler compounds physically • Can be broken down chemically (electrical current and H2O)
You should know this…. • Chemical bonds hold the elements of a compound together • Covalent bond • Shared electrons • STRONG BONDS • Form molecules
Still on bonding….. • Ions & Ionic Bonding • Atoms take or give up electrons • The resulting ion has either a + or – charge • NaCl Na + Cl- • Used to transmit signals in cells • Electrolytes • Held together by electrostatic forces • Disassociate in water
Energy and Rxn’s • Activation Energy- minimum amount of energy for a reaction to take place • A candle won’t burn unless the wick is lit • Flame (energy) provides activation energy
Enzymes • Enzymes are biological catalysts • They lower the activation energy needed for a reaction to proceed • Most reactions in the human body need more energy than 37 0C can provide • Substrate- what the enzyme works on • Active Site- part of the enzyme perfectly matched to the substrate • Like a lock and key
Many things effect enzymes • Temperature- too high/low they don’t work • pH – too high /low they don’t work • Pepsin works best at a pH of 2. Where is it in your body? • What pH do most enzymes work best at? • Denature- the structure of the enzyme is permanently damaged and it will no longer work • Frying an egg
Water • Water is H2O • It is polar • The oxygen has a slight – charge • The hydrogen has a slight + charge
Acids and Bases • Most solutes can dissolve in water • Acids release H+ ions • Bases release OH- ions • Measured on the pH Scale
Organic Chemistry • All Biological elements contain carbon • Organic molecules contain carbon (CO2 is the exception) • Carbon is special: • It can bond with 4 different elements • It can bond with many different carbons • Carbon can form many shapes • Chains, branches, and rings
Biochem • Macromolecules- large organic molecules • Polymers- long chains of repeating units called monomers • Held together by covalent bonds • Cellulose, starch, DNA, and proteins are all polymers
Carbohydrates • Carbohydrates – carbon, hydrogen, and oxygen • Monosaccharide- simple sugars • Glucose • Disaccharide- 2 simple sugars bonded • Sucrose • Polysaccharide-polymers of sugars • Cellulose, starch, glycogen
Lipids • Lipids are mostly made of carbon and hydrogen • Triglyceride-type of lipid • Liquid in plants (oil) • Solid in animals (butter)
Saturated vs. Unsaturated Fats • Saturated • Can not bind to any more H • Solid • Unsaturated • Have a double bond and a kink • liquid
Phospholipids • Amphipathic- • Have a polar head • Non-polar tail • Component of cell membranes • Biological Barriers
Steroids • Cholesterol- makes cell membranes leaky • Estrogen- • Testostone-
Structure of Proteins • Proteins are polymers of amino acid • Proteins are made of Carbon, hydrogen, oxygen, nitrogen and sometime sulfur
Amino Acids • There are only 20 amino acids • All proteins are made out of different combinations of amino acids • Amino acids covalently bond to each other
Protein Structure • Amino acids fold into a 3-D shape • α-helix • β-pleated sheet • 3-D shape held together by hydrogen bonding • If the shape changes the protein does not function