Chapter 2-Basic Chemistry

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Chapter 2-Basic Chemistry

• Biology 112
• Tri-County Technical College
• Pendleton, SC

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Organic Compounds

• Text defines organic compound as containing
  carbon
• Where would one put CO2?
• Prefer to expand organic as containing both
  carbon and hydrogen(s)
• Carbohydrates, lipids, proteins, and nucleic
  acids are organic
• Water, salts, acids, and bases are inorganic

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Water, water everywhere

• Water is crucial to living systems
• High heat capacity
• Holds heat and releases it slowly
• Excellent solvent because of its polarity
• Involved in some reactions essential for life
• Protects certain organs (brain/spinal cord)

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Salts and Electrolytes

• Salts are ionic compounds anion (-) and cation
  ()
• Separate into ions when dissolved in water
• All salts are electrolytes because they conduct
  electrical current in solution
• Calcium and Phosphorus most plentiful
• Sodium and potassium essential to nerve impulses

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Acids with examples

• Acid is substance that can release hydrogen ions
  (H) in detectable amounts
• Also called proton donors
• Hydrochloric acid is good example
• HCl?H Cl-
• Other acids include acetic and carbonic
• Acids that release all their protons called
  strong acids
• Acids that ionize incompletely (acetic/carbonic)
  are called weak acids

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Whos on first?

• Base is known as proton acceptor
• Hydroxides common inorganic bases
• Release hydroxyl ion (OH-) into solution
• NaOH?Na OH-
• Any base containing this ion is strong base
• Bicarbonate ion (HCO3-) is weak base
• When acids and bases mixed water and a salt
• HCl NaOH? H2O NaCl
• Neutralization reaction

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pH and more

• pH stands for potential hydrogen and is measure
  of s of hydrogen ions in various fluids
• Number of protons in solution expressed in terms
  of moles per liter
• pH of 7 has equal amounts of protons and hydroxyl
  ions and is NEUTRAL
• Neither acidic nor basic

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pH, continued

• pH lower than 7 acidic
• pH higher than 7 basic
• Lets be real careful with our verbalizations
• pH scale is LOGARITHMIC
• BUFFER is substance that can react with strong
  acid or base to form weaker acid or base and thus
  resist changes in pH

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More on buffers

• Blood ph normally 7.35-7.45
• Changes of more than few tenths of pH unit auf
  wiedersehen
• Important buffering systems of human body include
• Protein buffering system
• Carbonic acid-bicarbonate buffering system
• Phosphate buffering system

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Organic compounds and Life

• Four classes of organic compounds essential
  to/for life
• Carbohydrates, lipids, proteins, and nucleic
  acids
• All are macromolecules (polymers)
• Review polymers are constructed of identical or
  similar repeating subunits called monomers

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Carbohydrates

• Includes the starches and sugars
• Contain carbon, hydrogen, and oxygen
• Translated into hydrated carbon
• Ratio of 2 hydrogen atoms to one oxygen atom
• Consists of the mono, di, and polysaccharides
• Left out the oligosaccharides for good reason
  (3-20)

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Monosaccharides

• One or simple sugar
• Ratio of CxH2xOx
• Glucose (hexose) is blood sugar and universal
  cellular fuel
• Fructose, galactose, ribose and deoxribose are
  important monosaccharides

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Disaccharides

• Di means two or double sugar
• Important disaccharides include sucrose
  (glucose/fructose), lactose (glucose/galactose),
  and maltose (glucose/glucose)
• REVIEW dehydration synthesis (condensation
  reaction) and hydrolysis
• Chalk talk time on wheres the water?

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Polysaccharides

• Poly means many
• Long branching chains of linked simple sugars
• Starch is plant form of carbohydrate storage
• Glycogen is animal store form
• Short supply stored in liver/muscle cells
• Cellulose is most abundant organic material on
  Earthcare for some fiber?

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Lipids

• Includes the neutral fats, phospholipids, and
  steroids
• Contain C, H, and Os but C and Hs far outnumber
  the Os
• Tristearin C57H110O6
• Most lipids insoluble in water but dissolve in
  other lipids and organic solvents such as
  alcohol, ether, and acetone

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Lipids, continued

• Neutral fats (triglycerides) composed of glycerol
  and fatty acids (chalk talk time)
• Are bodys most abundant and ed source of
  usable energy
• Phospholipids (chalk talk time again)
• Phosphate part always charged giving it special
  properties
• Review hydrophilic versus hydrophobic
• Major part of cellular membranes

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Steering the steroids

• Basic structure of three 6- and one 5-carbon
  rings
• Fat soluble
• Cholesterol?vitamin D, sex hormones, cortisol,
  and bile salts
• Atherosclerosis (deposits of fatty substances
  on artery walls and Arteriosclerosis (hardening
  of arteries)
• Some anabolic steroids, guys?????

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Proteins, fibrous and globular

• Account for gt 50 of organic matter in body
• Constructive materials, cell function,
  metabolism, and protection
• C, H, O, and N (sometimes S)
• Polymers constructed of monomers of amino acids
  (20 common to living systems)
• Chalk-talk time againYEAH!!!!

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Proteins, continued

• AA chains of less than 50 AAs called polypeptides
  (lets not get picky)
• FIBROUS proteinsstructural proteins
• Collagen (most abundant protein in body) found in
  bones, cartilage, and tendons
• Keratin hair, nails, and skin tougher
• GLOBULAR proteinsfunctional proteins
• Motile, play role in nearly all biological
  processes although quite unstable
• Antibodies, hormones, enzymes

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Enzymes and more

• Are functional proteins that act as biological
  catalysts
• Catalyst is substance that gts rate of reaction
  without becoming part of product or being changed
  itself
• Chalk-talk time on substrates, active site,
  apoenzyme, holoenzyme, competitive and
  noncompetitive inhibition

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Enzymes, continued

• Most named according to specific type of reaction
  catalyzed
• Hydrolases add water
• Oxidases cause oxidation (what it are?)
• In most cases, if it ends in ase it is an
  enzyme
• For all intents and purposes, if one does NOT
  have the enzyme, one is NOT going to run the
  reactionenough said

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The nucleic acids

• DNA (deoxyribonucleic acid) is the genetic
  material
• RNA (ribonucleic acid) responsible for protein
  synthesis
• Monomers of both are NUCLEOTIDES
• Generic nucleotidefive carbon sugar (pentose),
  one of 4 nitrogenous bases, and a phosphate group

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Oh, she has her mothers eyes

• DNA nucleotide has deoxyribose sugar A,T,G, or
  C and phosphate
• Double stranded with strands held together by H
  bonding
• Genetic material that contains info directing
  protein synthesis
• All we really got from our parents was info on
  how to make proteins
• My daddy had his bald head when we buried himI
  got some DNA from him for baldness

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Ribonucleic Acid (RNA)

• Nucleotide of RNA contains ribose sugar, A, U, G,
  or C, and phosphate
• NO thymines in RNA (uracil)
• Always constructed single stranded but may double
  back on itselfglobular shape
• Does actual job of protein synthesis
• mRNA, tRNA, rRNA
• Pass the chalk, please!

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Some critical concepts

• Bases are complementary
• In eucaryotes, DNA found in nucleus
• Chromatin versus chromosome
• RNA puts together proteins (translation) in the
  cytoplasm from info copied from DNA
  (transcription)
• ATP (adenosine triphosphate) is energy coin of
  the realm
• Adenine base, ribose, and 3 phospates
• ADP-ATP cycle (energy coupling)

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ATP
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ATP drives cellular work
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Moving Right on Along into Chapter 3