Upload
jasmine-smith
View
219
Download
2
Embed Size (px)
Citation preview
Chp. 5 - Organic Chemistry
Structure and Function of Macromolecules
AP Biology
Vocabulary Check
SIZE prefixes• Mono
– One
• Poly– Many
• Di– Two
Miscellaneous• Lysis = to break
BIOMOLECULE roots• Sacchar-
– Sugar– End in -ose
• Peptide– Protein– Enzymes: end in -ase
• Lipid– Fat
The synthesis and breakdown of polymers
Dehydration Synthesis & Hydrolysis
• Building bigger molecules– Dehydration synthesis– Removing water to create a
bigger molecule
• Breaking up big molecules– Hydrolysis– Uses water to break apart a
big molecule into subunits
Building and Breaking MoleculesDehydration Synthesis vs. Hydrolysis
OH OH OH
+ +
H H H
OH
H
2H2O
Explanation: 3 Glucose molecules (monomers)bind to create a Starch molecule (polymer).
DehydrationSynthesis
OH OH OH
+ +
H H H
OH
H2H2O
Hydrolysis
Explanation: A starch molecule (polymer) becomes the glucose (monomers)that make it up.
What does this look like in sugars?
• Dehydration Synthesis Reaction– Carbons are numbered (for ease)– Links can be made between different carbons– Glycosidic linkage is a covalent bond between 2
monosaccharides
Carbohydrates
• Energy Source– Cell processes require energy– Mono/disaccharides– Polysaccharides – stored energy (starch for plants,
glycogen for animals)
• Carbon Source– Structure; building material (cellulose for plants)– Can be used to construct amino acids and fatty
acids
Monosaccharide Characteristics
• Ring structure
• Formula = C6H12O6
• Generally sweet• Examples: glucose, fructose, galactose, ribose,
deoxyribose• Function = Source of quick energy or raw
material for creating other molecules
Disaccharide Characteristics
• 2 ring structure with a glycosidic linkage
• Formula = C12H22O11
• Generally semi-sweet• Examples: sucrose, maltose, lactose• Function = Source of fairly quick energy or
raw material for creating other molecules
Polysaccharides: Starch vs. Cellulose
• Both are chains of glucose
• Cellulose does not dissolve in water (cotton does not dissolve when you wash it)
• You use starch as an energy source via respiration
• You do not have the enzyme to digest cellulose
What are Lipids?
• Hydrophobic molecules (have a “fear” of water)
• Most diverse biomolecule category. Examples:– Fats– Phospholipids– Steroids– Waxes & Pigments
Lipids • Fats (triglycerols)
• Energy storage in animals. • Fat cells are designed for continuous
synthesis and breakdown of triglycerols, controlled mainly by the activation of hormone-sensitive enzyme lipase.
• Provides high caloric content, about 9 kcal/g, compared with 4 kcal/g for the breakdown of carbohydrates and proteins.
• Migratory birds that must fly long distances without eating use stored energy of triglycerols to fuel their flights.
Saturated vs. Unsaturated
• Saturated• As many hydrogen as
possible are bonded to the carbon chain.
• Solid at room temp.• Unsaturated• One or more double
bonds forms a kink.• Liquid at room temp.
Saturated vs. Unsaturated Fats
SATURATED• All single bonds• Straight shape, compact• Solid at room temp.
– Ex. Butter, lard
UNSATURATED• Include 1+ double bond• Kinked shape, not
compact• Liquid at room temp.
– Ex. Vegetable oil
Phospholipids (cell membranes)• Carbon chain is non-polar (doesn’t dissolve in water)• Phosphate is polar (dissolves in water)
Phospholipids
• Major part of cell membranes• Structure:
– 2 Hydrophobic tails – Hydrophilic head – In a bilayer
Steroids• Carbon rings are non-polar• Non-polar means hydrophobic
Steroids• Regulate organism functioning• Structure: 4 fused rings with different side groups• Note: change in side groups = change in function
What’s Up with Proteins?
• Amino Acid/peptide = the monomer of proteins
• Amino acids join by peptide bonds into a polypeptide
• A protein is more than just a chain of polypeptides– Shape is essential!!
COMPONENTS:
• Amine group (NH2)
• Carboxyl group (COOH)
• R group (different for each of 20 amino acids)
Protein (amino acid + amino acid + amino acid, etc.)
Are proteins diverse?
• A 20 letter “alphabet”
• Proteins can be 100s or 1000s of “letters” long– Imagine the
diversity!
Protein Functions• Structure – support (connective tissue, webs)• Storage – store amino acids; egg white, milk, seeds• Transport – hemoglobin (carries oxygen), channels
(H+ through ATP synthase)• Hormonal – regulation; insulin• Receptor – Na+ and K+ receptors in nervous system• Contractile – movement (actin/myosin in muscle)• Defense – antibodies fight bacteria/viruses• Enzymes – speed up chemical reactions
4 levels of Protein Structure
• Primary– Unique sequence of amino acids
• Secondary– Hydrogen bonds create coils and folds– Alpha helix– Beta pleated sheets
• Tertiary– Irregular contortions do to side chain (disulfide bridges)
• Quaternary – Two or more polypeptides joined together
Levels of Protein Structure
• Primary (1°)—amino acid sequence• Secondary (2°)—folds/coils of amino acid
change caused by hydrogen bonds• Tertiary (3°)—interactions between R groups• Quaternary (4°)—2+ polypeptides that form
one functional protein
Primary Structure
Secondary Structure
Tertiary Structure
Quaternary Structure
What are Nucleic Acids?
• Information Storage Molecules– Consist of other molecules
• Deoxyribose or Ribose sugars• Phosphate groups (also in some lipids)• Nitrogenous bases
– Store the blueprints that make the proteins that create your traits!