Macromolecules Packet #8 12/2/2018 12:57:43 AM

CARBOHYDRATES

Carbohydrates Mainly used for energy Also known as General Formula Sugars Saccharide Starches General Formula CnH2nOn When n = 3 Called a triose sugar Glyceraldehyde When n = 5 Called a pentose sugar Ribose When n = 6 Called a hexose sugar Glucose 12/2/2018 12:57:43 AM

Monosaccharide There is only one sugar Examples Glucose Fructose Galactose Have the same basic formula C6H12O6 12/2/2018 12:57:43 AM

Monosaccharide Have different arrangement of the atoms They Isomers Aldose Glucose Ketose Fructose They All reduce Benedict’s reagent A solution of sodium citrate, sodium carbonate, and copper sulfate that changes from blue to yellow or red in the presence of reducing sugars, such as glucose. are sweet Soluble Easily transported Main respiratory substrates. 12/2/2018 12:57:43 AM

Monosaccharides

Monosaccharides

Monosaccharides Trioses Glyceraldehyde Aldose sugar The phosphorylated form is the first formed sugar in photosynthesis May be used as a respiratory substrate or converted to starch for storage Intermediate in the Kreb’s Cycle (Cell Respiration) Dihydroxacetone Ketose sugar Respiratory substrate Intermediate in the Kreb’s Cycle Remember, the arrangement of atoms are different 12/2/2018 12:57:43 AM

Monosaccharides Pentoses Ribose/Deoxyribose Aldose sugars Makes up part of nucleotides Gives structural support to the nucleic acids RNA & DNA Component of hydrogen carrier NAD NADP FAD Component of ATP Ribulose Ketose sugar Carbon dioxide acceptor in photosynthesis 12/2/2018 12:57:43 AM

Monosaccharides Hexoses Glucose Aldose sugar Major respiratory substrate in plants and animals Used in the synthesis of disaccharides and polysaccharides Component of nectar Galactose Respiratory substrate Used in the synthesis of lactose Fructose Ketose sugar Used in the synthesis of insulin Sweetens fruits to attract animals to aid in seed dispersal 12/2/2018 12:57:43 AM

Glucose Hexose sugar Aldose sugar The presence of all the oxygen molecules ensure that glucose is strongly hydrophilic Remember, that oxygen is very electronegative and helps increase the polarity of an atom Contain a lot of energy in their bonds

Glucose Structure You should already be familiar with the linear form However, glucose also is shown in a ring form There are two different ring structures Isomers α glucose β glucose

Alpha & Beta Glucose

Linear & Ring Structures of Glucose

Polymerization Monosaccharides, a monomer, and other organic compounds, can be combined/linked together by a chemical process known as polymerization to form polymers. Di-saccharides Sucrose Glucose & Fructose joined together Polysaccharide Cellulose Several thousand glucose molecules joined together. 12/2/2018 12:57:43 AM

Polymerization—Dehydration

Disaccharides Formed by the condensation of any two monosaccharide Glucose + glucose =maltose (malt sugar) Glucose + fructose = sucrose (cane sugar) Glucose + galactose = lactose (milk sugar) Basic formula C12H24O12 Some reduce in Benedict’s solution Maltose Others are non-reducing sugars Sucrose All are sweet, soluble in water and are readily converted into monosaccharides by the addition of a water molecule Hydrolysis 12/2/2018 12:57:43 AM

Disaccharides Sucrose Lactose Maltose Glucose+ Fructose Respiratory substrate The form in which most carbohydrates are transported in plants Storage material in some plants Allium - onions Lactose Glucose + Galactose Mammalian milk contains 5% lactose Major carbohydrate source for sucklings Maltose Glucose + Glucose 12/2/2018 12:57:43 AM

Polysaccharides Vast majority of carbohydrates in nature are found in the form of very large polymers made up by the joining of various monosaccharides. Glucose is the most abundant sugar used in making these large polymers Most polysaccharides are polydisperse Even when in a pure form, any given sample of the substance will vary in its size and the number of monomer units in its structure Starch may have any where between 100 and 10,000 glucose monomers in a chain

Polysaccharides Starch Made by plants as a way of storing chemical energy Major storage carbohydrate in plants Comes in two forms Amylose Amylopectin Long unbranched chain of -glucose molecules Unbranched chain of -glucose with 1,4 glycosidic links Plus branched chain of -glucose units with 1,4 and 1,6 glucosidic links Branches occur every 24-20 units along the chain 12/2/2018 12:57:43 AM

Alpha & Beta Glucose & Polymers

Starch

Cellulose Cellulose Most commonly found in plants Probably* the most prevalent and abundant source in nature Possible that 50% of all of the organic carbon, on the planet, is in the form of glucose Most commonly found in plants Gives structural support to cell walls Is in its purest form in cotton Homework What are the advantages of cotton containing 90% cellulose? Formed when -glucose molecules are joined together using their 1st and 4thcarbons Unbranched chain of -glucose units with 1,4 glycosidic links + cross bridges Reaches lengths of between 300 and over 2000 units

Cellulose

Polysaccharides Glycogen Animal equivalent of starch Major storage carbohydrate in animals and fungi Found in the liver and muscles Branched molecule Highly branched chains of -glucose units with 1,4 glycosidic links New branch occuring every 10 or so units along the chain 12/2/2018 12:57:43 AM

Polysaccharides Chitin A tough, protective, semitransparent substance, primarily a nitrogen-containing polysaccharide, forming the principal component of arthropod exoskeletons and the cell walls of certain fungi. Forms the basis of the hard shells of crustaceans Crab; lobster; shrimp Long unbranched molecule consisting of -glucose molecules are joined together using their 1st and 4thcarbons May be thought of as cellulose in which the hydroxyl groups on the second carbon are replaced with NHCOCH3 groups

Chitin Monomer

Chitin

LIPIDS

Lipids I Contain carbon, hydrogen and oxygen Does not contain as many oxygen molecules as carbohydrates Formed via a condensation reaction and broken apart via hydrolysis Composed of two parts Glycerol Head Hydrophilic Fatty acids Tail Hydrophobic Some lipids have one of the fatty acids replaced by phosphoric acid These are called phospholipids Very important component of the cell membrane 12/2/2018 12:57:43 AM

Lipids

Glycerol A syrupy, sweet, colorless or yellowish liquid, C3H8O3, obtained from fats and oils as a byproduct of saponification and used as a solvent, an antifreeze, a plasticizer, and a sweetener and in the manufacture of dynamite, cosmetics, liquid soaps, inks, and lubricants. A reaction in which an ester is heated with an alkali, such as sodium hydroxide, producing a free alcohol and an acid salt, especially alkaline hydrolysis of a fat or oil to make soap.

Lipids II Can be divided into two types Fats Solid at room temperature Oils Liquid at room temperature Saturated Fats vs. Unsaturated Fats Saturated A molecule that has only single bonds Found largely in animals Unsaturated A molecule that has one or more multiple bonds Largely comes from plants Better for your health because the ”kinks” prevent the fat molecules from packing closely together. Helping reduce heart disease 12/2/2018 12:57:43 AM

Kinks

Lipids III Energy Storage Structural Support Insulation Waterproofing Fats are stored for future energy use Structural Support Phospholipids Critical component of the cell membrane Insulation Especially useful where hair and feathers are of little use Example Underwater Blubber in whales Waterproofing Waxes Leaf cuticles are made of waxes Secreted from sebaceous glands of the skin 12/2/2018 12:57:43 AM

Phospholipids Found at the surface of cells Four main components Glycerol Fatty acids PO4 {Phosphate/Phosphate Group} Organic molecule 12/2/2018 12:57:43 AM

Phospholipid

Phospholipid

Phospholipid Bi-Layer

Phospholipid Bilayer

NUCLEIC ACIDS

Nucleic Acid Nucleic Acids are composed of nucleotides Nucleotide Three main components Nitrogenous base Adenine; Guanine; Cytosine; Thymine; Uracil Uracil is only found in the Nucleic Acid RNA Thymine is only found in the Nucleic Acid DNA Sugar Deoxyribose; Ribose Phosphate group Polynucleotides More than one nucleotide joined together DNA & RNA 12/2/2018 12:57:43 AM

Nucleotides

DNA/RNA