Presentation on theme: "GRADE 12 BIOLOGY (SBI4U) MACROMOLECULES. 2 Macromolecules: What you need to know! 1. Structure of the basic unit (carbohydrates, lipids, proteins, nucleic."— Presentation transcript:
2 Macromolecules: What you need to know! 1. Structure of the basic unit (carbohydrates, lipids, proteins, nucleic acids) 2. How they react to form larger molecules 3. How the larger molecules are broken down into basic units 4. Functions of the molecules in living organisms
Start with water, add lots of small carbon-containing molecules and ……. Macromolecules are the molecules of life! 14 Macromolecules: Why do we care? How do you build a cell? use these four major classes of macromolecules
Macromolecules 15 All living things are made of cells Cells are: ~72% H 2 O ~3% salts (Na, Cl, K…) ~25% carbon compounds (macromolecules)
“Condensation” or “Dehydration” Synthesis (aka polymerization) why synthesis? – a polymer grows in length (a new bond is made) why dehydration (or condensation) – formation of a water molecule MAKE
“Addition” polymerization monomer molecules added to a growing polymer chain NO molecules are eliminated in the process monomer is unsaturated (e.g., had a double bond) after an addition reaction it becomes saturated MAKE Can we add a monomer to a polymer without losing a water molecule?
Hydrolysis (Cleavage) hydrolysis (hydro = water, lysis = break) – reverses the process of dehydration by breaking down the polymer with the addition of water molecules BREAK
Carbohydrates (sugar/starch) Monosaccharide (b/w 3-7 carbon atoms) - Contain multiple hydroxyl groups and a carbonyl group – the simplest sugars glucose fructose, galactose ribose deoxyribose - Contains C, H, O in ratio of 1:2:1 21
Isomers Isomers – one of two or more molecules with the same number and type of atoms, but different structural arrangements e.g. glucose, fructose, galactose - Also differ in chemical and physical properties 22
Animal vs. Plant Fats Animal FatsPlant Fats - Triglycerols containing mostly saturated fatty acids -triglycerols are unsaturated and polyunsaturated FA - Straight hydrocarbon chains allowing for van der Waal attractions -Hydrocarbon chains have double bonds and many kinks, ↓ van der Waal attractions - Solid at room temperature- Liquid at room temperature
Proteins Proteins are used for: structure metabolism (enzymes) immunological protection molecular transport Proteins are made of subunits of amino acids. Proteins are the most diverse class of macromolecules due to 20 available amino acids.
Essential vs. Non-essential Amino Acids Essential Amino Acids: Cannot be produced by the body, therefore must be consumed in ones diet 8 essential Amino Acids Non-essential Amino Acids: Can be produced by the body 13 Non-essential Amino Acids
Tertiary (3 ° ) Structure provides protein a final 3-D structure four major bond types between R groups of amino acids 1. H-bonding 2. ionic bonding 3. hydrophobic interactions 4. covalent bond (disulfide bridge)
General Protein Shapes Globular Proteins (Hemoglobin) Fibrous Proteins (Tropomyosin & Keratin)
Quaternary (4 ° ) Structure fully functional protein requires all subunits present not all proteins have quaternary structure
Protein Properties Proteins have optimal conditions at which they function. When exposed to extreme conditions, proteins begin to unfold – denature. If denaturation occurs moderately over time, returning to the original conditions may result in renaturation.
Protein Folding Proper folding in the cell is completed by chaperonin molecules. Utilizes ATP to help proteins fold properly.
Nucleic Acids Nucleic acids are used for: maintaining genetic continuity delivering information for protein synthesis energy molecule (ATP – adenosine triphosphate) Two major nucleic acid polymers: 1. DNA – deoxyribonucleic acid 2. RNA – ribonucleic acid
Nucleic Acids DNARNA located in the nucleus double-stranded, double helix structure stable molecule mainly found in cytoplasm single-stranded structure unstable molecule
Nucleotides The basic subunit of nucleic acids is a nucleotide. Three components: 1. phosphate 2. pentose sugar 3. nitrogenous base
Nucleic Acid reaction between 1. pentose sugar OH group of one nucleotide 2. phosphate group of another nucleotide forms phosphodiester bond
In Conclusion The building blocks (monomers) of macromolecules are amino acids, nucleotides, simple sugars, and fatty acids
In Conclusion Name the two main chemical reactions shown making and breaking organic molecules
In Conclusion Carbohydrates are use for energy storage and as structural materials Lipids are used as energy storage and structural components Proteins are made of amino acids which form structures, enzymes, transport, movement, and are part of the immune system Nucleic acids are the basis of inheritance and reproduction
In Conclusion The versatility of carbon makes possible the great diversity of organic molecules Variation at the molecular level lies at the foundation of all biological diversity
MacromoleculeExample(s) of subunits Main functionsExamples of macromolecules carbohydratessugars (such as glucose) and polymers of glucose energy storagesugars, starches, and glycogen lipidsglycerol and three fatty acids or glycerol and two fatty acids energy storage and cell membranes fats, oils, and phospholipids proteinspolymers of amino acidstransport, blood clotting, support, immunity, catalysis, and muscle action hemoglobin, fibrin, collagen, antibodies, enzymes, actin, and myosin nucleic acidspolymers of nucleotidestransfer and expression of genetic information DNA and RNA 67 Answers to post-presentation activity #1 – the activity could be use alone as a pre-assessment (what should be known from Grade 11 SBI3U)
In building large macromolecules carbon usually combines with other carbons … AND with one or more functional groups 69
70 Why study Functional Groups? These are the building blocks for organic molecules (or macromolecules – large organic molecules)
the components of organic molecules most commonly involved in chemical reactions the number and arrangement of functional groups give each organic molecule unique properties Why study Functional Groups?
72 Types of functional groups 6 functional groups most important to chemistry of life: hydroxyl amino carbonyl sulfhydryl carboxyl phosphate
73 Functional groups they affect reactivity (e.g., hydrophilic, increase solubility in water)
Hydroxyl organic compounds with OH = alcohols alcohols, carbohydrates, nucleic acids, some acids, and steroids highly polar (makes molecules more soluble) e.g., ethanol
75 Carbonyl if C=O at end molecule = aldelhyde if C=O in middle of molecule = ketone react with molecules (H-R 2 ) to form H-R 2 -C-OH a ketone and an aldehyde may be structural isomers with different properties, e.g., acetone and propanal
76 Carboxyl compounds with COOH = acids fatty acids, amino acids acidic – tends to lose a proton (COO - ) involved in peptide bonds e.g., acetic acid - gives vinegar its sour taste
77 Amino compounds with NH 2 = amines amino acids, nucleic acids NH 2 acts as base - can pick up a proton (H + ) from the surrounding solution (ionized) glycine (has amine and carboxyl groups) – replace an H with an R group to get an amino acid under cellular conditions
78 Sulfhydryl compounds with SH = thiols 2 sulfhydryl groups can interact to help stabilize protein structure (S-S, disulfide bonds)
79 Phosphate compounds called organic phosphates Acidic – up to 2 negative charges when H + dissociates Links nucleotides in nucleic acids Energy-carrier group in ATP
2003-2004 83 Do the functional groups make that much difference? identical basic structure of male & female hormones attachment of different functional groups interact with different targets in the body
84 A Bit of Honey: Bee keeping was used in Crete over 4000 years ago to allow for the collection of honey, a highly prized food having great value in ancient civilizations Field bees gather the nectar, a sweet secretion in plant blossoms that contains fructose, glucose and sucrose Some worker bees secrete beeswax - Hexacosanoic acid, C 26 H 52 O 2, and triacontanol, C 30 H 62 O