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Chapter 3 Biomolecules pages 53-73. 99% of the mass of most cells is H, O, N, and C These are the smallest elements that can form 1,2,3 and 4 bonds. Required in grams/day Required in milligrams or less/day. Biomolecules are complex, but are made up of simpler components.
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Chapter 3 Biomolecules pages 53-73 99% of the mass of most cells is H, O, N, and C These are the smallest elements that can form 1,2,3 and 4 bonds. Required in grams/day Required in milligrams or less/day
Biomolecules are complex, but are made up of simpler components
Proteins, nucleic acids, polysaccharides and lipids are the most abundant biomolecules
Biomolecules are compounds of carbon Carbon atoms form 4 tetrahedral single bonds. Two carbon atoms sharing a single bond can rotate around the single bond.
Two carbon atoms sharing a double bond are closer and cannot rotate about the double bond. The carbons and the atoms bound to them form a plane.
Biomolecules are often made of carbon backbones with added functional groups, referred to as “R” groups
Functional groups can have chirality The central carbon (a-carbon) is a chiral center
Argininimide (colored) stereospecifically fitting within an RNA a pocket (grey)
Taste receptors can differentiate between diastereoisomers
Five main types of reactions in living cells • oxidation-reductions • cleavage and formation of C-C bond • internal rearrangements • group transfers • condensations- the joining of • monomers via the elimination of water
Oxidation reactions generally release energy. More reduced More oxidized
Reactions are catalyzed by enzymes in order to build biomolecules (anabolism, requires energy) and to degrade biomolecules (catabolism, produces energy). Figure 1-15 page 12
ATP synthesis is the central goal of catabolism Figure 1-10 Page 10 Terminal phosphoryl (shaded) can then be hydrolyzed.
ATP hydrolysis releases stored energy Figure 14-1 page 500
ATP hydrolysis can then be coupled with other reactions to produce a favorable overall reaction . Figure 1-9 Page 9
Pairs of electrons and hydrogens are often transferred in an oxidation-reduction
Cleavage and formation of C-C bond occurs via nucleophilic substitution reactions
Internal rearrangements occur due to sequential electron transfers
Amino acids, nucleic acids, sugars and lipids are the basic building blocks of biomolecules