Macromolecules

Biochemical ReactionsThe chemical reactions associated with biological processes1Learning FocusTo identify and describe the 4 main types of biochemical reactions: neutralization, oxidation-reduction,condensation, and hydrolysis reactions2What is a biological Rx?Any ideas? Generally 3 broad categories

metabolic rx any reaction in a living system.

Anabolic rx reactions that produce larger molecules.

Catabolic rx reactions that breakdown larger molecules.

If after neutralization reaction is complete, there are H ions left over the solution is acidic

If OH ions left over the solution is considered to be basic31. Acid-Base (neutralization rx)Neutralization Rx is a chemical reaction that occurs between an acid and a base (reactants), that results in water and a salt (products)

Result the acidic and basic properties of the aqueous solution where the reaction took place are nullified (i.e. cancelled out)

If after neutralization reaction is complete, there are H ions left over the solution is acidic

If OH ions left over the solution is considered to be basic4Acid/Bases review:Review what is an acid?A substance that produces hydrogen ions (H+) when it dissolves in H2O

What is a base?A substance that produces hydroxide ions (OH-) when it dissolves in H2O

Note: a base can also be defined as a substance that accepts or reacts with H+

5pH scale review:Review what is the pH scale? Take a second to define and describe it.

Its a numerical scale ranging from 0 14 that is used to classify aqueous solutions as acidic, basic, or neutral.

6What is considered to be normal?The normal pH range of blood is 7.35 7.45Given this is blood considered to be acidic or basic (alkaline)?

What do you think the consequence is of blood pH falling below 7.0 or above 7.8?

Acidosis (7.3 or lower) versus alkalosis (7.5 or higher)

(you tube: precision nutrition kitchen tip)

Acidosis = is a condition in which there is excessive acid in the body fluids.7Consequences of pH imbalanceWith a pH higher or lower than normal range, blood cells will be damaged.Acids can denature or change the shape of proteins, same with heat or high temperatureStrong acids and lemon juice can be used to cook fish (cheviche) and eggsBases make oils and fats to fall apart.- e.g. bile in digestion; oven cleaners contain lye, a strong base that dissolve grease and burn fats in ovens

8Acid-base reactions in living organisms What do living cells use to resist changes in pH? (i.e. how do organisms neutralize acidic or basic environments?)

Buffers!A substance that minimizes changes in pH by donating or accepting hydrogen ions as needed9Acid-base reactions in living organisms Buffers are chemical systems that contain a substance that can donate H ions when they are required and contain a substance that can remove H ions when they are too many in solutionsBuffers usually consist of conjugate acid-base pairs in equilibriumCarbonic acid bicarbonate buffer is important in human extracellular fluid

- Our blood also helps to buffer some proteins can play same role10Lets take a look at the questions you answered so long ago!

Pg. 2311reactions involving electron transfer

2. Oxidation-reduction (Redox) Rx12Q: What reaction do you know of that would be classified as redox?- NaClOxidation = chemical reaction where an atom loses electrons

Reduction = chemical reaction where an atom gains elections

Therefore a REDOX reaction = a chemical reaction that involves the transfer of electrons from on substance to anotherRedox Reactions13How to remember what happens?Use mnemonic: LEO GERLossGainElectronElectronOxidationReduction

Redox Reactions LEO the lion says GER14Redox ReactionsReducing Agent substance that LOSES electrons; it causes the other substance to be reduced

Oxidizing Agent substances that GAIN electrons; it causes the other substance to be oxidizede.g. C3H8+ 5O2 3CO2 + 4H2O + energyCombustion of propane15Redox in the CellMany metabolic processes consist of chains of redox reactions.A-AB-BC-CDD-e.g. C6H12O6 + 6O2 6CO2 + 6H2O + energy16Involved in the assembly of all four types of biological macromolecules (as are Hydrolysis Rx)

= a chemical rx that results in the formation of a covalent bond between two molecules with the production of a water molecule3. Condensation Rx

17Q: What reaction do you know of that would be classified as redox?- NaCl Condensation Rx

18Q: What reaction do you know of that would be classified as redox?- NaClBecause the reaction involves a release of water, condensation rx are also called dehydration reactions

Always involves the removal of a H atom from the functional group of one monomer (or subunit) and an OH from the other monomers (or subunits) functional group

This type of reaction always absorbs energy

Also considered to be an anabolic reaction = synthesis of molecules

3. Condensation Rx19Absorbs energy so molecules being created end up storing a lot of energyAnabolic Rx in Nucleic Acids bond that forms from the dehydration reaction between 2 (or more) nucleotides is called a phosphodiester linkage;

occurs between the OH group of one nucleotide, and the phosphate group of the next

+ H2O20Anabolic rx in carbs

glucosefructosesucrose bond that forms from the dehydration reaction is a glycosidic bond; occurs between an OH group on each molecule involved in the reactionpass around molecules for students to practice condensation and hydrolysis reactions21Anabolic rx in fatsglycerol + 3 fatty acid fat (triglyceride)

22Anabolic rx in fats

bond that forms from the dehydration reaction in the creation of a fatty acid is an ester linkage; occur between the OH group on a glycerol molecule and the COOH group on a fatty acid23Anabolic Rx in Proteins

bond that forms from the dehydration reaction between 2 (or more) Amino acids is called a peptide linkage or bond; occurs between the carboxyl of one AA and the amino group of another24Involved in the breakdown of macromolecules into their monomers (smaller subunits)= a chemical rx that results in the cleavage of a covalent bond with the addition of a water molecule

This type of reaction always releases energy

Also considered to be an catabolic reaction = breaking down

4. Hydrolysis Rx25Q: What reaction do you know of that would be classified as redox?- NaClMacromolecules:What you need to know!Structure of the basic unit (carbohydrates, lipids, proteins, nucleic acids) (what are the monomers)

How they react to form larger molecules (what are the polymers) (examples)

How the larger molecules are broken down into basic units

Functions of the molecules in living organisms

26Testing Carbohydrates27Benedicts Testtesting for reducing sugars

Benedicts reagent is used to detect reducing sugars. The blue-coloured, copper-based solution will produce a red to orange precipitate in the presence of a reducing sugar and heat.Demo in class28Starch Testtests for the presence of starch

Lugols iodine is a yellow solution that will turn a dark purple / black colour in the presence of starch molecules.29Testing for Proteins30Biurets Testtesting for the presence of proteins

Biurets solution is a blue-coloured, copper-based solution that turns purple in colour in the presence of protein.31Testing for Lipds32Sudan Testtesting for the presence of lipids

Sudan dye is a water-insoluble, black-red dye that will stain solutions containing lipids a red colour.

Gizmo demo/assignmentSudan dye is a carcinogen33