A large chemical compound with covalent bonds MACROMOLECULES

Refresher Polymer Monomer A long chain-like molecule composed of many smaller linked molecules Monomer A small molecule; when linked together, monomers form polymers

QUIZ!!! What does the term macromolecule mean? What is the relationship between monomers and polymers? What are the four biologically important types of molecules?

Carbohydrates Importance: Made in photosynthesis Source of energy, building materials, and cellular identification

Carbohydrates

Carbohydrates Structure: Found in a ratio of 1:2:1 of carbon, hydrogen, and oxygen Can be structural isomers (molecules with the same chemical formula but with a different arrangement of atoms – fructose & glucose) Found in a straight chain if they are dry and in a ring if they are wet

Carbohydrates Classification Monosaccharides Oligosaccharides One sugar (aka. Simple sugar) Quick source of energy & building blocks for polysaccharides (ie. Glucose/dextrose, fructose, galactose) Oligosaccharides Short chain of monomers bound with glycosidic linkages Polysaccharides 100-1000 monomers in a chain used for energy storage (starch & glycogen (liver & muscle cells)) or structural support (cellulose & chitin (surgical thread))

Carbohydrates Page 34 #2, 3, 5, 8

Lipids Hydrophobic (hating water) Triglycerides Structure A type of lipid consisting of three fatty acids bonded to a glycerol molecule (fats & oils) Structure Saturated: only single bonds allowing the maximum number of hydrogens Unsaturated: containing double or triple bonds so the maximum number of hydrogens cannot bind Hydrogrenation is a process of adding hydrogens to fatty acids to make them more saturated (byproduct = trans fats)

Lipids

Lipids Importance: Storing energy Building membranes & cell parts Stores twice as much energy as equal masses or carbohydrates or protein Building membranes & cell parts Aid in absorbing vitamins and minerals Chemical signaling Brain growth Hormones Cushion and insulation

Lipids Families Phospholipids (two fatty acids and a phosphate containing group bonded to a glycerol) Found in cell membrane because of their polar head (hydrophilic) and nonpolar tail (hydrophobic) creating a bilayer in water Steroids Compact hydrophobic molecules with four fused hydrocarbon rings and functional groups (cholesterol, testosterone, estrogen) Waxes Long chain fatty acids linked to alcohols or carbon rings making them pliable but firm and effective for water proofing

Lipids Phospholipid

Lipids Page 40 #13, 15, 16

Nucleic acids Importance Store hereditary information DNA is located in the nucleus but RNA can move between the nucleus and the cytoplasm (also functions in protein synthesis) The only molecule that can produce an identical copy of itself

Nucleic acids

Nucleic acids Structure Nucleotide: phosphate, sugar, base Made of nucleotides (monomer) joined with phosodiester bonds between the phosphate group and the hydroxyl group attached to carbon 3 of the sugar using an enzyme (creating the polymer nucleic acid) DNA’s bases are adenine, thymine, guanine, and cytosine RNA’s bases are adenine, uracil, guanine, and cytosine

Nucleic acids Phosphodiester bonds

Protein Importance: Structure (skin, bones, ligaments, tendons) Enzymes Immune response Transport Clots Cellular identification

Protein Structure Amino acids bound by peptide bonds (long chains of amino acids are called polypeptides) 20 different R-groups (like letters of the alphabet)

Protein Levels of structure: Primary structure (amino acid sequence) Secondary structure (alpha helix or beta pleated sheet) Tertiary structure (folding based on bonding between remainder groups) Quaternary structure (clumping between two or more polypeptides)

Protein

Protein A protein’s shape determines its function therefore they are very sensitive to conditions that may change their shape Changes in temperature or pH may cause the protein to denature (ie. cooked chicken) Bonds break and reform differently changing the shape of the protein and making it non functional It can return to its original shape as long as the primary structure remains intact

Protein Page 50 #19, 26

Review

Macromolecules in cells