CHEMISTRY

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CHEMISTRY

• CHAPTER 2

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Basic concepts in Chemistry

• Matter-anything that occupies space and has
  weight. Three states of matter-solid, liquid and
  gas. The amount of matter is termed-mass.
• Elements-smallest unit of matter. There are 92
  naturally occurring elements. Chemical symbols.
  Refer to tab2-1 pg. 32 for elements present in
  the living organism and their significance.

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ATOMS

• Atoms-smallest unit of element that retains
  properties of the element.
• nucleus and electron cloud
• electrons, protons and neutrons
• atomic number and mass number
• isotopes
• energy levels

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Atoms

• Ions charged atoms. Cations and anions
• Molecules combination of two or more atoms with
  a bond.
• Free radicals
• compounds a substance that can be broken to two
  or more elements. eg. water.

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Chemical Bonds

• Ionic Bondattraction between two oppositely
  charged atoms (ions), cation and anion.
• Covalent bondbond formed by sharing of
  electrons.
• Hydrogen bond a weak attractive force between
  hydrogen of one molecule and oxygen or nitrogen
  of another.

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Chemical Reactions

• Definition when new bonds form and old bonds
  break between atoms.
• reactants and products
• metabolism-anabolism and catabolism
• work
• energy- kinetic and potential
• endergonic vs. exergonic

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Types of Reactions

• Decomposition AB------gtA B-catabolism
• synthesis A B --------gt AB-anabolism
• exchange AB CD --------gt AC BD
• reversible A B -------gt AB
• redox loss of electrons oxidation
  
• gain of electrons-reduction

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Inorganic compounds

• Water and its properties
• high heat capacity
• surface tension
• good solvent
• hydrolysis reactions
• lubricant
• aqueous solutions all nutrients etc. carried in
  the blood in the form of aqueous solutions.

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Acids, Bases Salts

• acids, bases and salts
• acids are substances that release hydrogen ions.
• Bases are substances that release hydroxyl ions
  or accept hydrogen ions.
• Salts release ions other than hydrogen or
  hydroxyl.
• pH-measure of hydrogen ion concentration in the
  solution. It is a negative log scale. Acids have
  pH below 7 and bases have pH above 7.

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Buffers

• These are substances that resist changes in pH.
• Made of a combination of a weak acid or base and
  its salt.
• Convert strong acids to weak acids and strong
  bases to weak bases.
• Most common base found in the living system is
  made of carbonic acid and bicarbonate.

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Organic Chemistry

• Study of carbon and its compounds.
• Organic compounds are largely made of carbon and
  hydrogen. They are complex structurally and held
  together by covalent bonds.
• Carbon skeleton and major functional groups.
• Monomers, polymers, and isomers.

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Organic compounds

• For each organic compound know what it is, the
  major elements, the major types, examples,
  functions, where it is located in the body and
  foods that contain it. Also be able to recognize
  them given the structure.
• Four organic compounds are carbohydrates,
  lipids, proteins and nucleic acids.

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Carbohydrates

• An organic molecule that contains the elements
  carbon, hydrogen and oxygen in the ratio 121.
  Also termed sugars.
• Types monosaccharides (glucose, fructose),
  disaccharides (sucrose, maltose) and
  polysaccharides (starch, cellulose and glycogen).
• Energy source, energy storage, stuctural support.
• Foods-

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Lipids

• Organic molecules with the elements C, H and O
  that are insoluble in water. Ratio is not 121.
  
• Lipids are classified into-fatty acids,
  triglycerides, steroids, phospholipids,
  prostaglandins.
• Energy source, energy storage, insulation, cell
  membrane components, hormones.
• Foods

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Proteins

• Organic polymers of amino acids with the elements
  C, H, O, N.
• peptide bond
• proteins are classified based on their function
  -support, movement, transport, buffering,
  metabolic regulation, hormones, defense.
• Structural organization of proteins- primary,
  secondary, tertiary and quaternary.
• Denaturation-loss of function due to loss of
  shape.
• Foods

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Enzymes

• Definition organic catalysts that speed up
  chemical reactions by lowering activation energy.
• substrate and products
• names end with the letters -ase.
• activation energy-energy required to start a
  reaction.
• enzyme activity-lock and key model and
  induced-fit hypothesis.
• factors that affect enzyme activity temperature,
  pH, metals, coenzymes.

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Nucleic Acids

• Organic polymers of nucleotides with the elements
  C, H, O, N and P.
• the major types are RNA and DNA.
• DNA -genetic information.
• RNA-protein synthesis.
• Differences between RNA and DNA.

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Adenosine Triphosphate (ATP)

• This is the energy molecule of life.
• Mostly generated in the mitochondria of each
  cell by cellular respiration.
• Liberates energy by removal of one or two
  terminal phosphate groups.
• ATP-----gt ADP P energy
• ADP P energy--------gt ATP. Catalyzed by ATP
  synthase.