Chemistry of Life

UNIT 2 - BIOMOLECULES Compare the structure/function of the major biological molecules (carbohydrates, proteins, lipids, nucleic acids) as related to the survival of living organisms. Explain how enzymes act as catalysts for biological reactions. Understand enzymes are necessary for all biochemical reactions and have a general understanding of how enzymes work in terms of the connection between shape and function.

BIOMOLECULES ORGANIC = ___________________________________ N H C S OH all contain carbon as backbone N H C S OH C SINGLE BOND C C C H DOUBLE BOND TRIPLE BOND RING STRUCTURE

BIOMOLECULES MONOMER POLYMER LARGER MOLECULES ATOMS MOLECULES one part CARBOHYDRATE many parts single molecule, repeating unit of polymer larger molecule, made of many repeating units (monomers) LIPID PROTEIN NUCLEIC ACID

1C:2H:1O CARBOHYDRATES CONTAIN – CARBON, HYDROGEN, & OXYGEN MONOMER = POLYMER = MONOSACCHARIDE DISACCHARIDE POLYSACCHARIDE glucose sucrose starch lactose fructose glycogen galactose cellulose KNOW FUNCTIONS OF EXAMPLES IN YELLOW chitin deoxyribose ribose

LIPIDS N0N-POLAR HYDROPHOBIC (does not mix with water) Triglycerides (fats & oils) long-term energy storage, insulation, cushioning/protection Waxes protection, prevent drying out / keep dry Phospholipids main component of cell membrane chemical messengers, cholesterol, sex hormones (estrogen, testosterone) Steroids

LIPIDS FATS - Triglycerides – OILS - solid, saturated fatty acid tails, animals (lard, butter) GLYCEROL FATTY ACID FATTY ACID FATTY ACID OILS - double bond liquid, unsaturated fatty acid tails, plants (vegetable oils) What is the difference between a saturated fatty acid & an unsaturated fatty acid? unsaturated saturated

PROTEINS Monomer – amino acid peptide bonds Polymer – polypeptide joined together by Polymer – polypeptide Large 3-D molecule that undergoes folding and bending of the polypeptide. Shape is determined by the ____________ and ____________ of amino acids. number sequence Examples: structure – hair, fingernails, horns, and hoofs muscles – contract for movement immune system – antibodies, fight infections hormones – chemical messengers receptor sites – part of cell membrane; other molecules attach to them insulin – regulates blood glucose levels hemoglobin – part of red blood cells; carries oxygen to cells

regulate all biochemical reactions in an organism PROTEINS ENZYMES regulate all biochemical reactions in an organism BIOLOGICAL CATALYST speeds up chemical reaction by lowering activation energy METABOLISM ENZYME…… NOT PART OF CHEMICAL REACTION KEEPS SHAPE RE-USED LOCK AND KEY MODEL

PROTEINS ENZYMES

NUCLEIC ACIDS DNA – RNA – deoxyribonucleic acid 2 strands double helix carries genetic information; controls what occurs in cells 2 strands double helix RNA – ribonucleic acid involved in making proteins 1 strand

NUCLEIC ACIDS nucleotide monomer = P P DNA A (adenine) C (cytosine) Each nucleotide is composed of: 5-carbon sugar (ribose or deoxyribose) phosphate molecule P nitrogenous base DNA A (adenine) C (cytosine) G (guanine) T (thymine) RNA A (adenine) C (cytosine) G (guanine) U (uracil) complementary base pairs A - T C - G

Functions of macromolecules Carbohydrate  energy, some structure/support Proteins  structure, growth, repair, enzymes, hormones, carry oxygen, regulate glucose Lipids  long term energy storage, cushioning, insulation; hormones; prevent drying out/getting wet; cell membranes Nucleic Acids  store genetic information as code; involved in making proteins

Food Tests Benedict’s solution is a test for monosaccharides. It starts blue and turns red if heated. Why did the sucrose remain blue after being heated?

Food Tests Iodine is a test for starch. It starts as a rust color and turns black or blue/black.

Food Tests Lipids turn brown paper translucent.

Food Tests Proteins Biurets turns purple when proteins are present.