BIOCHEMISTRYThe chemistry of Life
Chemicals that make up living things are mostly organic macromolecules belonging to the four groups
Carbohydrates
proteins
lipids
nucleic acids
http://mset.rst2.edu/portfolios/a/abdelmessih_m/finalproject/biochempro.ppt
Organic Molecules
Structure monomers polymers
Carbohydrates C,H,O
1:2:1
monosaccharides Polysaccharides
Proteins C,H,O,N,S Amino Acids Polypeptides
Lipids C,H,O Fatty Acids Complex fat
Nucleic Acids C,H,O,N,P Nucleotides RNA, DNA
Carbohydrates• Carbohydrates have the general formula of(CH2O)n, with abundant
hydroxyl groups(-OH). • Carbohydrates can be either a single sugar, (Click) monosaccharide
like glucose, (Click) a disaccharide like sucrose, or a series of monosaccharides
(Click) polysaccharides like Starch.
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•glucose, "blood sugar", the immediate source of energy for cellular respiration •galactose, a sugar in milk (and yogurt), and •fructose, a sugar found in honey.
Although all three share the same molecular formula (C6H12O6), the
arrangement of atoms differs in each case. Substances such as these three, which have identical molecular formulas but different structural formulas, are known as isomers.
Monosaccharides
Back Carbohydrates
+
Sucrose
Condensation Hydrolysis
Two monosaccharides can be linked together to form a "double" sugar or disaccharide by Condensation reactionThe reverse reaction is Hydrolysis where sucrose molecule is broken down into two monosaccharides, glucose and fructose.
Back Carbohydrate
+ H2O
http://www.tvdsb.on.ca/Westmin/science/sbioac/biochem/condense.htm
http://trc.ucdavis.edu/biosci10v/bis10v/media/ch02/reaction_types.html
Polysaccharides
Complex molecules composed of three or more monosaccharides
GlycogenStores glucose in animals
in the form of highly branched chain,used for quick energy.
StarchStores glucose in plant in the form of
Highly branched chain
Coiled unbranched chain
CelluloseIn the form of straight chains linked
together by hydrogen bonds.Gives rigidity and strength
to plant cellsBack Carbohydrates
Proteins Macromolecules or polymers constructed from one or more unbranched chains of polypeptide .A polypeptide chain is composed of amino acids. A typical protein contains 200–300 amino acids
The protein represented here consists of two polypeptide chains, a long one on the left and a short one on the right.
Amino acids (Click) are the building blocks (monomers) of proteins. 20 different amino acids are used to synthesize proteins. The shape and other properties of each protein is dictated by the precise sequence of amino acids in it.
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*** The important example of proteins are (Click) Enzymes.
Hydrogen
Carboxyl Group
Amino Group
Functional Group
The basic structural of an Amino Acid
VALINE
ALANINE
GLYCINE
Back TableAmino acids are joined together by a (Click) peptide bond. Back Proteins
Amino acids are joined by condensation and a water molecule is removed. It is formed as a result of a condensation reaction between the amino group of one amino acid and the carboxyl group of another.The bond formed as a result between the two amino acids is called a peptide bond and the product is called dipeptide.
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Back Proteins
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http://student.ccbcmd.edu/biotutorials/proteins/peptide.html
http://michele.usc.edu/java/pept.html
http://plantsciences.montana.edu/cqlab/proteinformation.htm
Enzymes Enzymes are (Click) catalysts. Most are proteins. Enzymes bind temporarily to one or more of the reactants of the reaction they catalyze. In doing so, they lower the amount of activation energy needed and thus speed up the reaction
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In order to do its work, an enzyme must unite with at least one of the reactants(substrate). This requirement for complementarity in the configuration of substrate and enzyme explains the remarkable specificity of most enzymes. Generally, a given enzyme is able to catalyze only a single chemical reaction
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Enzymes are organic molecules that act as catalysts. They speed up chemical reactions by decreasing
the amount of activation energy.
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LipidsLarge, nonpolar organic molecules that do not dissolve in water. They have higher ratio of carbon hydrogen bonds ( that store energy) than carbon oxygen bonds.Most lipids are composed of (Click) fatty acids.
(Click) Phospholipids
Lipids
(Click) Waxes
(Click) Steroids
Complex Lipids
(Click) Triglycerides
Cholesterol
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A fatty acid is a long unbranched carbon chain with carboxyl group –COOH attached to one end.
A carboxyl group (polar,attracted to water molecules)Hydrophilic
Ahydrocarbon end(nonpolar,interact With water molecules) hydrophobic
UnsaturatedCarbon atoms make double bond.
Saturated fatty acidCarbon atoms make single bonds.
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TriglyceridesThree molecules of fatty acids + a glycerol molecule
Saturated Triglycerides Unsaturated Triglycerides
Saturated fatty acids
Solid at room temperature
Ex. Animal fats
unsaturated fatty acids
Liquids at room temperature
Ex. Plant seed & fruitsBack Lipids
Two molecules of fatty acids + a glycerol moleculePhospholipids
Our cell membranes are made mostly of phospholipids arranged in a double layer with the tails from both layers “inside” (facing toward each other) and the heads facing “out” (toward the watery environment) on both surfaces( lipid bilayer). The membrane serves as barrier between the inside and outside of the cell
Hydrophilic Head
Hydrophobic Tails
Hydrophilic Head
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http://www.wisc-online.com/objects/ViewObject.aspx?ID=ap1101http://www.susanahalpine.com/anim/Life/memb.htm
Steroids
Composed of four fused carbon rings with various functional groups
Ex. **cholesterol
**many animal hormones like the male hormone testosterone.
WaxesLong fatty acid chain+Long alcohol chain.It forms protective layer in animal and plants
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Nucleic Acids Very large molecules(polymers) that store genetic information.They composed of linked monomers called (Click) nucleotides.
DNADeoxyribonucleic acid
contains information for all cell activities
RNARibonucleic acid
stores and transfer the information for protein production
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