Crossroads Academy 5th Grade
Intro to Organic Compounds
Organic Compounds
l Contain the element carbon l Are essential to life l Come in 4 main classes:
l Proteins l Lipids l Carbohydrates l Nucleic Acids
What makes organic compounds so diverse?
l Carbon can bond at 4 different sites because it has 4 valence e-
l Carbon can single, double and triple bond
l Carbons can bond to each other in chains, branches or rings
Polymers l Most organic compounds are polymers
l Polymers are BIG molecules made of repeating smaller molecules (“sub-units”)
l Each subunit is called a MONOMER
l When many MONOMERS join together to form a large chemical chain it is called a POLYMER
NOW LET’S LOOK AT ACH TYPE OF ORGANIC MOLECULE MORE CLOSELY
Carbohydrates l Sugars and starches l Made of monomers called
monosaccharides – Ex. Fructose and Glucose – Animals use Glucose for energy in their cells.
Monosaccharides are the building blocks of carbohydrates
POLYSCCHARIDES l Polysaccharides are carbohydrate polymers l They are made by joining MANY
monosaccharides – Ex. Starch, Cellulose and Glycogen
Lipids l Fats, oils and waxes
l Lipids are hydrophobic because they are non polar.
l Phospholipids are important lipids found composing the cell membrane
Fats are Triglycerides l They are made of a Glycerol backbone
joined to 3 fatty acid tails
l Can be saturated with H atoms or can be unsaturated due to the presence of double bonds in the fatty acid tails.
Saturated vs. Unsaturated Fats
Comparison of Fats Saturated l Contain only single bonds in
C backbone l H fills ALL empty spotsè
Saturated with Hydrogen l Uniform shape allows easy
stacking l Solid at room temp. l Can clog blood vessels l Less healthy fats l Ex. butter or lard
Unsaturated l Contain only double or
triple bonds bonds in C backbone
l Less H needed because some spots are taken by double bonds
l Bent shape due to double bonds prevents stacking
l Liquid at room temp. l More healthy fats l Ex. Olive oil or vegetable
oil
Proteins l Proteins are REALLY diverse! l Muscles, hair, enzymes, keratin in skin….. l Are polymers made of sub-units called
AMINO ACIDS l There are only 20 amino acids but they
combine to make all of the proteins in the world!
l Covalent bonds that hold amino acids together are called PEPTIDE BONDS
Proteins get folded into shapes!
Nucleic acids l Are Polymers made of sub-units called
NUCLEOTIDES
l RNA, DNA and ATP are nucleic acids
l The code of life is written in the pattern of nucleotides on DNA
l Nucleic acids control the synthesis of proteins
Organic Compounds LAB
l Your Goal: 1.) To test known compounds to determine a
positive test for Sugar, Starch, Lipid, and Protein
2.) To use knowledge gained above to determine the identity of unknown compounds.