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Chemistry. The Basics. Matter- anything that takes up space and has mass Elements- substance that cannot be broken down into simpler substance with different properties Atoms- smallest part that displays properties of element Composed of electrons, protons, neutrons.
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The Basics • Matter- anything that takes up space and has mass • Elements- substance that cannot be broken down into simpler substance with different properties • Atoms- smallest part that displays properties of element • Composed of electrons, protons, neutrons
Atomic Number- # of protons Atomic Mass- # of protons + # of neutrons Isotope- atoms with different # of neutrons
Bonding Elements are usually most stable with 8 electrons in outer shell Compound- 2 or more elements bonded together Molecule- smallest part of a compound Formula- shows how many of each element
Ionic bonding- giving away/ gaining electrons, causes charged elements called ions
Water Hydrogen bond- attraction of slightly + H with slightly – O, many together can be quite strong Responsible for many of water’s unique properties Living things are composed of 70-90% water, making it the most important compound for life
High heat capacity-water takes 2x as much heat to raise its temp 1 degree. It takes a lot of energy to go from liquid to gas Temperature of water rises and cools slowly (organisms can adjust) High heat of evaporation-allows for sweating
Cohesive(sticks to itself) and Adhesive(sticks to other objects)
Acids/Bases pH scale- amount of H+ ion available. More H+ ion lower pH- Acid Less H+ (more OH-) higher pH- Base(alkalines)
Buffers Maintain pH within narrow range (7.3-7.4 for humans)
Organic Molecules • Contain both C and H atoms • Four classes • Carbohydrates • Lipids • Proteins • Nucleic Acids
Why Carbon? Only 4 electrons in outer shell- can bind with up to 4 other elements/ creates diversity CHNOPS (most commonly bonded to) Can form both linear and ring structures
Functional groups A specific combination of bonded atoms that functions the same way regardless of the particular carbon skeleton.
Isomers Organic molecules have identical molecular formulas, but different shapes React differently in chemical reactions
Rearranging molecules Dehydration synthesis
Carbohydrates Immediate energy source Structural component of cells Can occur as single monomers (monosaccharides) or as polymers (polysaccarides)
Monosaccharides Simple sugars CH2O Glucose, fructose, galatose, ribose Cellular fuel
Disaccharide 2 monosaccharides Sucrose (used to sweeten foods) Lactose (milk)
Polysaccharides • Polymers (3 or more simple hooked together) • Starch- glucose storage in plants • Glycogen-glucose storage in animals • Cellulose- structural carbohydrates in plants • Chitin- cells walls and exoskeletons • Peptidoglycan- bacterial cell walls
Lipids Insoluble in H2O Usually very large Composed of long chains Combine fatty acids – COOH and glycerol 3 –OH groups (water soluble)
Triglycerides • Fats- solid at room temperature (come from animal products) • Oils- liquid at room temperature (come from plant products) • Stores much more energy than carbohydrates
Phospholipids Found in plasma membranes A polar end and non-polar end
Steroids Four fused carbon rings and differs by the functional groups attached Cholesterol- animal plasma membrane/ physical stability Testosterone/estrogen- hormones Waxes- hydrophobic and resistance to breakdown
Proteins • Structure and function • Transport • Metabolism • Regulation • Support • Defense • Motion
Peptides 2 or more amino acids bonded together, polypeptide many bonded together Each polypeptide has its own sequence, which leads to a particular shape If the shape changes, so does the function
Amino Acids Contain an amino group (-HN2) and an acid group (-COOH)
Protein Structure Primary structure- amino acid chain Secondary structure- alpha helix, Beta sheets Tertiary structure- final folding Quaternary structure- 1 more proteins together
Nucleic Acids DNA, RNA, coenzymes, ATP Composed of nucleotide (sugar, phosphate group, nitrogen base)
DNA Double helix- composed of 2 strands with complementary base pairing A-T , C-G The order of the bases is important DNA is self-replicating (occurs before mitosis)
RNA • Single stranded • Contains the base uracil in place of thymine • Found both in nucleus and cytoplasm • 3 types • Messenger • Ribosomal • Transfer
DNA-RNA-protein DNA codes for proteins One gene codes for one protein DNA to RNA- transcription RNA to protein- translation
ATP • Adenine, ribose and 3 phosphate groups • Last 2 phosphate bonds are unstable and easily broken, releasing energy