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Lipids •Parts of triglyceride •Function of triglycerides •Phospholipids •Steroids Carbohydrates •Characteristics & Isomers •Mono-, di-, & PolyNucleic Acids •Structural components •Characteristics Reading Ch 4-5: Lipds, Carbs & Nucleic Acids Ch 6: The Cell Homework Ch 6 Prequiz Ch 7 Prequiz Diffusion & Osmosis Prequiz VIDEO! Homework 1 Fibrous and Globular Proteins • Fibrous proteins – Extended and strand-like proteins – Water insoluble – Examples: keratin, elastin, collagen, and certain contractile fibers • Globular proteins – Compact, spherical proteins with tertiary and quaternary structures – Water soluble (more or less) – Examples: antibodies, hormones, and enzymes Phenylalanine is: a)Polar b)Charged + c)Charged d)hydrophobic e)None of the above Many Globular proteins change shape This structure is an example of ___ structure? a)1° b)2° c)3° d)4° e)5° Example of a transmembrane domain Highly hydrophobic side chains Binding of the red molecule gives an alternative protein structure. What level of protein structure is this? a)1° b)2° c)3° d)4° e)5° What is breaking and reforming to allow this rearrangement? a)Covalent b)Ionic c)Hydrogen d)Hydrophobic e)Van der waals Shape changes Mostly / usually alters hydrogen bonding pattern Different composition means another more thermodynamically stable shape When O2 binds to hemoglobin, the protein changes shape. This is an example of what level of protein structure? a)Primary b)Secondary c)Tertiary d)Quatenary How would you expect 2 proteins to interact with each other? Primarily through: a)Covalent b)Ionic c)Hydrogen d)Hydrophobic e)Van der waals Lipids •Contain C, H, and O, but the proportion of oxygen in lipids is less than in carbohydrates therefore hydrophobic / Insoluble in water Soluble in other lipids and organic solvents Lipids are therefore a less cohesive / broad category Functional Groups – a)Carboxyl b)Amino c)Ester d)Methyl e)phosphate Lipids: Triglycerides oils (liquid) & fats (solid) For energy storage 2 Major categories of Fatty acids Solids = Fats Saturated with H’s Liquids = oils mono-UNsaturated Trans vs Cis Lipids: Triglycerides oils (liquid) & fats (solid) Joining is through? a)Condensation b)Hybridization c)Hydrolysis d)redox II . Phospholipids Can vary Serine, etc. Esterification Alcohol + acid Phosphodiester bond The Cell Membrane In water/solution phospholipds will spontanesouly form 19 Membrane Lipids • 75% phospholipids (lipid bilayer) – Phosphate heads: polar and hydrophilic – Fatty acid tails: nonpolar and hydrophobic • 5% glycolipids – Lipids with polar sugar groups on outer membrane surface • 20% cholesterol – Increases membrane stability and fluidity Steroid hormones Testosterone Estradiol (Estrogen) chenodeoxycholic acid (bile salt) Lipids Summary Triglycerides Function: food storage composition: 1 glycerol (know structure) 3 Fatty acids (carboxyl on unbranched hydrocarbon) Saturated vs unsaturated (Cis vs Trans) Phospholipids Function: membranes due to amphipathic structure Composition: 1 glycerol, 2 fatty acids, 1 phosphorous group Cholesterol Function: membranes & hormone precursor Know general structure: 4 rings Carbohydrates • Sugars and starches Food & structural – Main function to be degraded and used as energy • Very soluble – many OH’s trademark of carbs • Contain C, H, and O general formula: [(CH20)n] • Three classes – Monosaccharides – Disaccharides – Polysaccharides Alcohol groups & Aldehyde or ketone Aldose sugar Ketose sugar Aldehyde group ketone group Glucose C6H12O6 Fructose C6H12O6 Fig. 5-3 Many isomers Same formula (C6H12O6) different structure Isomers of glucose 1 2 D-Glucose Enantiomer of D-Galactose Sugars in solution forms ring (>90%) 1 2 or Have some idea of electron pushing 1 2 4 Note numbering Dehydration synthesis (condensation) -Galactose to form glycosidic bonds Glucose 1–4 glycosidic linkage Glucose Glucose Maltose 1–2 glycosidic linkage Glucose Fructose Sucrose Lactose glycosidic bonds Carbohydrate to “x” to Hemiacetal of a saccharide R-OH •Starch-plant storage – less branched •Glycogen – animal storage (liver & muscles) – more branched •Cellulose – plant polysaccharide – undigestible – different structure (bonding) •Chitin – modified glucose - acetylated Glycogen & starch Cellulose Polysaccharides Energy Starch Structural Type Unit Bonding Glycogen (animal) α-glucose 14 & 16 highly branched Amylose (Plant) α-glucose 14 non-branched Amylopectin (Plant) α-glucose 14 & 16 branched Cellulose (Plant) β-glucose 14 non-branched Most predominant biological material in world Fig. 5-10 (a) The structure of the chitin monomer. (b) Chitin forms the exoskeleton of arthropods. (c) Chitin is used to make a strong and flexible surgical thread. • Chitin, another structural polysaccharide, is found in the exoskeleton of arthropods • Chitin also provides structural support for the cell walls of many fungi Carbohydrates Summary Function: Energy Part of nucleic acids (ribose, deoxyribose) Structural (Cellulose, chitin) Composition: Many hydroxyl groups General formula [(CH20)n] Differences in monosaccharides – structural - isomers Cyclization in solution vs β Specific Sugars to know Monosaccharides – Glucose, Galactose, Fructose Disaccharides – Maltose (glu-glu), Sucrose (glu-fru), Lactose (gal-glu) Polysaccharides Glycogen & Starch - α-glucose 14 & 16 branched Cellulose - β-glucose 14 unbranched Chitin Maltose is composed of? a)Glucose b)Fructose c)Sucrose d)galactose Maltose linkage? a)1-4 Glucose b)1-4 α-glucose c)4-6 α-glucose d)1-4 β-glucose Which of the following is an amino acid? A) C) D) B) Various biological molecules can be combined Glycolipids Glycoprotein Lipoprotein A T G C A G T c C G A . . G A A C G G C A A T G A C A T G A T C C A T A C A . . . . T G C A A C A A G A G . . . Nucleic acids store and transmit hereditary information • The amino acid sequence of a polypeptide is programmed by a unit of inheritance called a gene • Genes are made of DNA, a nucleic acid Outside Nucleus Giant Library of Code (DNA) Inside Cytoplasm The Roles of Nucleic Acids • There are two types of nucleic acids: – Deoxyribonucleic acid (DNA) – Ribonucleic acid (RNA) • DNA provides directions for its own replication • DNA directs synthesis of messenger RNA (mRNA) and, through mRNA, controls protein synthesis • Protein synthesis occurs in ribosomes Fig. 5-26-3 DNA 1 Synthesis of mRNA in the nucleus mRNA NUCLEUS CYTOPLASM mRNA 2 Movement of mRNA into cytoplasm via nuclear pore Ribosome 3 Synthesis of protein Polypeptide Amino acids Sugar phosphate backbone 5’ o 1’ 4’ 3’ for RNA Variable nitrogenous base deoxy 2’ for DNA Base Phosphate groups H Ribose Deoxyribose Nomenclature Nucleosides Adenosine Guanosine Thymidine Cytidine Uridine With ribose Adenine Phosphate groups Ribose Adenosine Adenosine monophosphate (AMP) Adenosine diphosphate (ADP) Adenosine triphosphate (ATP) Nomenclature Nucleosides Adenosine Guanosine Thymidine Cytidine Uridine With deoxyribose Adenine Phosphate groups H Ribose Deoxyribose deoxy Adenosine deoxy Adenosine monophosphate (dAMP) deoxy Adenosine diphosphate (dADP) deoxy Adenosine triphosphate (dATP) Polymerization New nucleotide Ch 16 G A T C 4 Nucleotides molecules with: same “backbone” different “bases” 5’ G Arranged in any order backbone 3’ A G T C A T base C 3’ G C A T T 5’- TGGAGTCCTTGTAGAGCATATGAG-----3’ G Or uracil H Bases “fit” together G bonds to C A bonds to T G A C T DNA is double stranded Strands are complimentary Held together by hydrogen bonds 1. Complementary Strand Pi C G Pi Pi Pi Pi Pi Pi Pi Pi 3’ Pi G Pi C 3’- C T A Pi G 3’ Pi T Pi Pi T - 3' 5’ Pi A T 5’ C A 5’- G A - 5' What is the complimentary strand? 5’-GGGAAATGC-3’ a) 5’-GGGAAATGC-3’ b) 3’-GGGAAATGC-5’ c) 5’-CCCTTTACG-3’ d) 3’-CCCTTTACG-5’ What is DNA for? Central Dogma Blueprint 1. To be copied and stored 2. To make RNA & Protein DNA Temporary copy Transcribe scribe RNA Protein = product High-energy phosphate bonds can be hydrolyzed to release energy. Adenine Phosphate groups Ribose Adenosine nucleoside Adenosine monophosphate (AMP) Adenosine diphosphate (ADP) Adenosine triphosphate (ATP) Coenzyme A (respiration) cAMP (signaling) Function: Nucleic Acid Summary Central Dogma: DNA RNA Protein Energy: ATP Other: signaling, coenzymes Composition: Backbone: Sugar – ribose in RNA, deoxyribose in DNA (1 fewer OH’s) Phosphate Variable Nitrogenous Base: A, T (U), G, C with 1 (pyrimidine) or 2 rings (purines) Double Stranded (DNA) or Single Stranded (RNA) anti-parallel Base Pairing (complimentary) - A:T(U), G:C [by hydrogen bonding] Nomenclature: Generic: (Nucleotide TriPhosphate) NTP (RNA), or dNTP (DNA) NDP (diphosphate) NMP (monophosphate) Specific: RNAs (ATP, UTP, CTP, GTP) DNAs (dATP, dTTP, dCTP, dGTP)
