p. 51 - MACROMOLECULES Carbon-based molecules Found in all living things Building blocks of cells Made up of the elements: Carbon (C), Hydrogen (H), Oxygen (O), Nitrogen (N), Phosphorus (P), and Sulfur (S)

There are 4 major macromolecules: Carbohydrates  CHO Lipids  CHO Proteins  CHONS Nucleic Acids  CHONP In many macromolecules, small molecules are subunits of an entire molecule, like links in a chain or beads in a necklace Monomer = 1 subunit (like a bead in a necklace) Polymer = molecule formed by linking monomers (the whole necklace put together)

Prefixes “mono” = one “poly” = many

p. 52 – Carbohydrates Monomer: monosaccharide (simple sugar) Function: Provides short-term energy Foods: breads, cereals, vegetables, fruits, & seeds Glucose is a common monosaccharide. Glucose = C6H12O6 Glucose

Many monosaccharides linked together make a polysaccharide Polysaccharide = polymer of monosaccharides Starches, glycogen, and cellulose are polysaccharides.

Types of Carbs Starch – food storage in plants Cellulose – structural support found in cell walls of plant cells (makes veggies crunchy) Glycogen – food storage in animals

p. 53 – Lipids Monomer: fatty acid Functions: provides and stores energy (long-term), cushions the body, and prevents heat loss Found in butter, margarine, oils Made of fatty acid molecules that consist of two distinct regions: a long hydrophobic hydrocarbon chain a hydrophilic head

Lipids Cell membranes are composed of phospholipids. Cholesterol is a lipid that has a ring structure. Steroid hormones, such as testosterone and estrogen, are also lipids. Lipids include saturated and unsaturated fats.

Saturated Fats Contain single carbon-to-carbon bonds Completely saturated with (has lots of) hydrogen Solid at room temperature (butter, lard, coconut oil, chocolate) Found in animal products Reduce Intake!  can clog blood vessels

Unsaturated Fats Contain double or triple carbon-to-carbon bonds Contains fewer hydrogen atoms Typically liquid at room temperature (oils, nuts, & avocado) Found in plant products Better for you than saturated fats!

Molecular structures of Fats Saturated Fat Unsaturated Fat

Lipids hate water = hydrophobic!!

DNA Structure discovery James Watson and Francis Crick with DNA Model in 1953.

p. 55 – Nucleic Acids Monomer: nucleotides composed of three parts Phosphate group Sugar (either ribose or deoxyribose) Base – there are 5 bases (cytosine, guanine, adenine, thymine, uracil) Function: stores genetic information There are two types: DNA (deoxyribonucleic acid) RNA (ribonucleic acid)

DNA – Deoxyribonucleic Acid DNA is the hereditary material passed on from parents to offspring Structure: double-stranded Phosphate group Sugar  deoxyribose Bases  Cytosine – Guanine Adenine – Thymine

RNA – Ribonucleic Acid RNA helps the DNA send messages throughout the cell Structure: single-stranded Phosphate group Sugar  ribose Bases  Cytosine – Guanine Adenine – Uracil

Nitrogenous Bases

p. 54 – Proteins Monomer: amino acid (there are 20 common ones) Function: provides structure, builds muscles, repairs body tissues Some are called hormones, enzymes, neurotransmitters, etc. Foods high in protein: meat, eggs, poultry, milk & milk products, nuts, dried beans, peas, & lentils

Peptide Bonds Amino acids are linked together by peptide bonds to form a polypeptide. Polypeptide = polymer of protein Water is released as a side product of forming the peptide bond.

Proteins Primary Structure The very basic strand of amino acids Secondary Structure The hydrogen-bond interaction among strands of amino acids giving alpha helices and beta-sheets shapes .

Proteins Interaction between alpha helices and beta-sheets. Tertiary Structure Interaction between alpha helices and beta-sheets. These protein domains allow folding for small globular proteins. Quaternary Structure Small globular proteins form protein aggregates. A famous example is hemoglobin.

Protein Structures

Protein Structures (Cont’d)

Macromolecules parts of the cell Membrane

p. 56 – Homework You only have 4 possible answers that can fill in the blanks: Carbohydrates Lipids Proteins Nucleic Acids