Biomolecules are any molecules that are produced by a living organism, including large macromolecules such as proteins, carbohydrates, lipids, and nucleicacids.
Carbohydrates'sugar' are the most common biomolecule.
Primary energy source for our body
Formula: CH2O
Building block/monomer: Monosaccharides
Elements: C-H-O
Classifications of Carbohydrates
Monosaccharides
Disaccharides
Polysaccharides
Monosaccharides (simple sugars) - C6H2O6
basic subunit of carbs
have polar hydroxyl (-OH) groups
A disaccharide will form if any two monosaccharides are joined
Monosaccharides are Glucose (blood sugar), Fructose (fruit sugar), Galactose (Found in milk with lactose)
Glucose + Glucose = Maltose (malt sugar)
Glucose + Galactose = Lactose (Milk sugar)
Glucose + Fructose = Sucrose (Table sugar)
Disaccharides (double sugars) - C12H22O11
Polysaccharides (complex sugars) - (C6H10O5)n, where n is the number of carbon atoms
Polysaccharides are starch, glycogen, cellulose and chitin
Starch
A polysaccharide made of alpha glucose molecules.
used for energy storage in plants
they provide a quickformofenergy for the body
examples: potato, pasta, and rice
Glycogen
used for energy storage in animals
when the body doesn't need glucose for energy it stores it in the liver
Cellulose
found in plants, in cell walls and bark of trees
gives us fiber
Chitin - forms the exoskeleton of certain insects and crustaceans
Tests for Carbohydrates
Iodine test
Benedict's test
Iodine test
used to determine the presence of starch in materials
a positive result is a change in color, ranging from violet to black
a negative result is yellow of the iodine solution
Benedict's test
used for simple carbs
Proteins
Body-building molecules which helps us grow
Transport molecules in and out of the cell
Controls the speed of chemical reactions
Building blocks: Amino acids
General formula: RCH(NH2)COOH, where R id a side chain, usually an amino acid
Elements: C-H-O-N
Proteins are albumin(egg whites), hemoglobin (blood), fibrinogen(clotting)
Tests for proteins
Biuret test
used to determine the presence of a peptide bond in a substance
the test yields a negative result if the biuret reagent changes from blue to purple
Nucleic acids
are not necessarily from food
biomolecular components of hereditary materials andare present in DNA and RNA
Building blocks: Nucleotides
Elements: C-H-O-N-P
Lipids
are also energy-giving molecules, but they are more commonly referred as the stored-energy molecules.
they store more energy than carbs and proteins
building blocks: fatty acids
general formula: CH3(CH2)n COOH
elements: C-H-O
Lipids provide mechanical protection for the internal organs of the body and serve as waterproof covering in some plants and animals
Examples of lipids: Steroids, cholesterol, fats, oils, nuts, waxes
Lipids are hydrophobic and don't dissolve in water
Saturated fat - solids
Unsaturated fat - liquid (oils)
Tests for lipids - Ethanol emulsion
Ethanol emulsion
ethanol is added to the sample
lipids are not present if the substance remains colorless and no emulsion is formed
lipids are present in the substance if a layer o cloudy white suspension forms above the solution
Saturated fatty acids
are straight-chain hydrocarbons with singlebonds between carbon atoms.
usually solid
produced by animals
Examples of animal fats are butter, lard, and tallow.
Unsaturated fatty acids
contain one or more double bonds
usually liquid
produced by plants
Examples are vegetable oil, corn oil, and olive oil.
Chemical reaction
New substances are formed when chemical bonds are broken and atoms rearrange to create newchemical bonds
Evidence of chemical reactions
Production of light
Evolution of gas
Temperature change
Change in intrinsic properties
Formation of a precipitate
Phlogiston theory
Theory that postulated a fire-like feature called Phlogiston within combustible bodies and releasedduringcombustion
There are 20 amino acids found in human protein
Isomers - compounds with the same molecular formulas but different structural formulas
Excess glucose is stored in the liver as glycogen for later use
Fructose - most sweetest naturally occurring sugar, found in fruits and honey
Condensation reaction - is a reaction in which two molecules or parts of the same molecule combine to form disaccharides, losing one molecule of water.