Macromolecules 1 Organic Compounds Compounds that contain CARBON
Macromolecules 1
Organic Compounds • Compounds that contain CARBON are called organic • Macromolecules are large organic molecules 2
Carbon (C) • Carbon has 4 electrons in outer shell. • Carbon can form covalent bonds with as many as 4 other atoms (elements). • Usually with C, H, O or N. N 3
Macromolecules • Large organic molecules. • Also called POLYMERS • Made up of smaller “building blocks” called MONOMERS 4
Examples of Macromolecules 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids (DNA and RNA) 5
How Are Macromolecules Formed? 6
Answer: Dehydration Synthesis • Also called “condensation reaction” • Forms polymers by combining monomers by “removing water”. HO H H 2 O HO H 7
Question: How are Macromolecules separated or digested? 8
Answer: Hydrolysis • Separates monomers by “adding water” HO H H 2 O HO H 9
Car boh ydr ate s 10
Carbohydrates • Small sugar molecules to large sugar molecules • Examples: A. monosaccharide B. disaccharide C. polysaccharide 11
Carbohydrates Monosaccharide: one sugar unit Examples: glucose (C ( 6 H 12 O 6) deoxyribose glucose fructose galactose 12
Carbohydrates Disaccharide: two sugar unit Examples: – sucrose (glucose+fructose) – lactose (glucose+galactose) – maltose (glucose+glucose) glucose 13
Carbohydrates Polysaccharide: many sugar units Examples: starch, glycogen, cellulose glucose glucose 14
Lip ids 15
Lipids • General term for compounds which are not soluble in water • Lipids are soluble in hydrophobic solvents • Remember: “stores the most energy” 16
Examples of Lipids Fats Phospholipids Oils Waxes Steroid hormones Triglycerides 17
Lipids Six functions of lipids: 1. Long term energy storage 2. Protect against heat loss (insulation) 3. Protect against physical shock 4. Protect against water loss 5. Chemical messengers (hormones) 6. Major component of membranes (phospholipids) 18
Lipids Triglycerides: composed of 1 glycerol and 3 fatty acids H = O H-C----O C-CH 2 -CH 2 -CH 2 -CH 2 -CH 2 -CH 3 O fatty acids H-C----O C-CH -CH = 2 2 2 CH -CH H 2 -C H 2 C Hglycerol 2 C H = = 3 19
Fatty Acids There are two kinds of fatty acids : 1. Saturated fatty acids: no double bonds (bad) = O C-CH 2 -CH 2 -CH 2 CH 2 -CH 3 saturated 2. Unsaturated fatty acids: double bonds (good) = unsaturated O C-CH 2 -CH=CH -CH 2 -C H 2 C H 3 20
Proteins 21
Proteins (Polypeptides) • Amino acids are the monomers (building blocks) that make up proteins 22
Amino Acid Structure 23
There are 20 different Amino Acids 24
• Six functions of proteins: 1. Storage: albumin (egg white) 2. Transport: hemoglobin 3. Regulatory: hormones 4. Movement: muscles 5. Structural: hair and nails 6. Enzymes: cellular reactions 25
Proteins (Polypeptides) Four levels of protein structure: A. Primary Structure B. Secondary Structure C. Tertiary Structure D. Quaternary Structure 26
Primary Structure Amino acids bonded together by peptide bonds to form a polypeptide chain Amino Acids (aa) aa 1 aa 2 aa 3 Peptide Bonds aa 4 aa 5 aa 6
Amino acids join together through dehydration reaction 28
Secondary Structure • 3 -dimensional folding arrangement of a primary structure into coils and pleats held together by hydrogen bonds • Two examples: Alpha Helix Beta Pleated Sheet Hydrogen Bonds
Tertiary Structure • Secondary structures bent and folded into a more complex 3 -D arrangement of linked polypeptides • Bonds: H-bonds, ionic, disulfide bridges (S-S) Alpha Helix Beta Pleated Sheet
Quaternary Structure • Composed of more than one polypeptide chain • Globular in shape • Form in Aqueous environments • Example: enzymes (hemoglobin) subunits
Protein structure 4 levels of protein structure Only some proteins have a quaternary structure 32
Nucleic Acids 33
Nucleic acids • Two types: a. Deoxyribonucleic acid (DNAdouble helix) b. Ribonucleic acid (RNA-single strand) • Nucleic acids are composed of long chains of nucleotides linked by dehydration synthesis 34
Nucleic acids • Nucleotides include: phosphate group pentose sugar (5 -carbon) nitrogenous bases: adenine (A) thymine (T) DNA only uracil (U) RNA only cytosine (C) guanine (G) 35
Nucleotide Phosphate Group O O=P-O O 5 CH 2 O N C 4 Sugar (deoxyribose) C 1 3 cmassengale Ccopyright C 2 Nitrogenous base (A, G, C, or T) 36
5 DNA double helix O 3 3 P 5 O O C G 1 P 5 3 2 4 4 2 3 P 1 T 5 A P 3 O O P 5 O 3 copyright cmassengale 5 P 37
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