Biochemical Reactions. First… a Summary Macromolecules Monomers + functional groups Four types of...

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Biochemical Reactions

Transcript of Biochemical Reactions. First… a Summary Macromolecules Monomers + functional groups Four types of...

Page 1: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Biochemical Reactions

Page 2: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

First… a Summary

MacromoleculesMonomers + functional groups

Four types of macromolecules of interest to us:CarbohydratesProteinsLipidsNucleic Acids

Page 3: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Carbohydrates

Monomer: simple sugar Ex. Glucose

Functional group(s): Carboxyl Hydroxyl

Polymer: complex CHO Starch, glycogen

Page 4: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Proteins

Monomer: amino acids 20 total, 8 or 9 essential

Functional group(s): Carboxyl Amino

Polymer Polypeptide Protein

Page 5: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Lipids

Monomer: Fatty acid Functional group(s):

Carboxyl

Polymers: many – depending on the type of lipid Phospholipid,

triglyceride

Page 6: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Nucleic Acids

Monomer: nucleotide A, T (or U), C, G

Functional group(s): Phosphate Amino Hydroxyl

Polymer: DNA and RNA

Page 7: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Biochemical Reactions

Chemical reactions associated with biological processes

Often involve a combination of more than one type of reaction

Four main types of reactions: Neutralization Oxidation-Reduction Condensation Hydrolysis

Page 8: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Acid-Base Reactions

Acid: produces H+ ions in waterpH value less than 7

Base: produces OH- ions in water or accepts H+ ionspH value more than 7

Neutralization Reaction: interaction of an acid and a base to form a salt (an ionic compound) and water

Page 9: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Neutralization Reaction

Necessary to maintain a constant pH state within the body

Buffers: resist changes in pH Release H+ ions when fluid is too basic Take up H+ ions when fluid is too acidic

Page 10: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Oxidation-Reduction Reactions

Involves the transfer of electrons Oxidation: loss of electrons Reduction: gain of electrons

Electrons are highly reactive and don’t exist on their own in cells If oxidation occurs to one molecule in the cell,

reduction must immediately to another molecule The entire reaction is often called a redox

reaction

Page 11: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Condensation Reactions

Involved in the assembly of all four types of macromolecules An H atom is removed from a

functional group on one molecule, and an OH group is removed from another molecule

Result: a larger molecule + water (water out, monomer in)

Also known as dehydration synthesis

Page 12: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Hydrolysis Reactions

Involved in the breakdown of macromolecules into their monomers Water is added to break the

bonds between monomers (water in, monomer out)

H from the water is added to one molecule, and the OH group is added to the adjacent monomer

Covalent bond between monomers breaks to form two smaller molecules

Page 13: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Role of Enzymes An enzyme is a biological catalyst

Speeds up a biochemical reaction, but is not used up in the reaction

Enzymes are proteinsHave a specific shapeEach enzyme fits specifically with a substrate

(the reactant for the reaction) to form an enzyme-substrate complex

Like a lock and key!

Page 14: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Enzyme-Catalyzed Reactions

Enzymes prepare substrates for reaction by changing the substrate, its environment, or both, in some way Causing bonds to stretch or bend (making them more

fragile) Bring two substrates together Transfer electrons to or from the substrate (i.e.

reduce or oxidize it), making it less stable Add or remove H+ ions to or from the substrate (i.e.

act like an acid or base), destabilizing it

Page 15: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Enzyme Denaturation

Proteins are called denatured when they have lost their shape. Caused by changes in temperature, pH, environmental factors,

etc. Because shape is so important to protein function, denatured

proteins are no longer able to carry out their proper function

Page 16: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Liver Functions

Page 17: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Importance of Catalase

H2O2 (hydrogen peroxide) is a harmful byproduct of many of the metabolic processes that take place in the liver Must be removed quickly This is the responsibility of the enzyme catalase

Page 18: Biochemical Reactions. First… a Summary Macromolecules  Monomers + functional groups Four types of macromolecules of interest to us:  Carbohydrates.

Factors Affecting the Action of Catalase

What might our liver be exposed to that