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Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Outline Chemistry of Carbon Macromolecules Protein  Amino Acids  Protein Shape Nucleic Acids  DNA and RNA Lipids Carbohydrates

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Chemistry of Carbon Organic Molecules are chemical compounds containing carbon.  Carbon atoms possess four valence electrons, thus can form four covalent bonds.  Hydrocarbons - Organic molecules consisting only of carbon and hydrogen. - Energy-rich

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Chemistry of Carbon Functional Groups - Groups of molecules that have definite chemical properties they retain no matter where they occur.

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Chemistry of Carbon Aldehydes and Ketones have a carbonyl group Aldehyde Ketone

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Chemistry of Carbon Biological Macromolecules  Proteins  Nucleic Acids  Lipids  Carbohydrates

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Macromolecules

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Building Macromolecules Cells assemble macromolecules via the removal of a molecule of water (Dehydration Synthesis).

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Building Macromolecules Cells disassemble macromolecules into constituent subunits via hydrolysis (Adding a molecule of water).

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Protein Functions Enzyme Catalysis Defense Transport Support Motion Regulation

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Amino Acids Build Proteins Amino Acid Structure  An amino acid is a molecule containing an amino group (-NH 2 ), a carboxyl group (-COOH), and a hydrogen atom, all bonded to a central carbon atom. - Each has unique chemical properties determined by the nature of the side group.

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Amino Acids Build Proteins Amino Acid Structure  20 Common Amino Acids grouped into five chemical classes, based on side groups: - Nonpolar amino acids - Polar uncharged amino acids - Ionizable amino acids - Aromatic amino acids - Special-function amino acids Exam 1 and notebook due on Friday for a progress report grade

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Amino Acids Build Proteins Proteins are polymers of amino acids.  Covalent bond linking two amino acids is called a peptide bond. - Protein is composed of one or more long chains, or polypeptides, composed of amino acids linked by peptide bonds.

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Protein Function and Shape Proteins consist of long amino acid chains folded into complex shapes.  Primary Structure - Specific amino acid sequence.  Secondary Structure - Folding of amino acid chain by hydrogen bonding into coils and pleats. - Motifs - Combinations of elements of secondary structure.

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Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Protein Function and Shape  Tertiary Structure - Final folded shape. - Positions various motifs and folds nonpolar side groups into the interior.  Stability of a protein is influenced by how well its interior fits together.  Quaternary Structure - A protein’s subunit arrangement.

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Protein Structure Copyright © McGraw-Hill Companies Permission required for reproduction or display

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies How Proteins Unfold Alteration of a protein’s environment may cause denaturation.  Usually renders protein biologically inactive.  Changes in pH, temperature, salt, etc. - Salt-curing and pickling food.

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Information Molecules Biochemical activity of a cell depends on production of a large number of specifically- sequenced proteins.  Nucleic acids are information storage devices, and serve as templates to produce precise copies of themselves. - Deoxyribonucleic acid (DNA) - Ribonucleic acid (RNA)

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Structure of Nucleic Acids Each nucleotide consists of :  Five carbon sugar  Phosphate  Organic nitrogen-containing base - Purines (Adenine and Guanine) - Pyrimidines (Cytosine, Thymine, Uracil)

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies

DNA Exists as double helix (winding staircase).  Base-pairs make up “steps”. - Base in one chain is attracted by hydrogen bonds of opposite base on other chain.  Hydrogen bonds hold two chains together.  Complementary base-pairing.  Stores hereditary material.

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies RNA Two major Differences from DNA:  Ribose is the 5-carbon sugar (in place of deoxyribose)  Uracil replaces Thymine. Typically single-stranded. Transcribes DNA information to direct protein synthesis.

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Lipids Lipids are a loosely defined group of molecules insoluble in water. Phospholipids form biological membranes.  Made of three subunits: - Glycerol - Fatty Acids - Phosphate Group  Contain polar head and non-polar tails.

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Fats and Other Lipids Fats consist of a glycerol molecule with three fatty acids attached Triglyceride (triglycerol).  Lack polar end, thus are insoluble in water.  Saturated Fat - All internal carbon atoms in fatty acid chains are bonded to at least two hydrogen atoms.  Unsaturated Fat - Contain double bonds between one or more pairs of successive carbon atoms.

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Fats and Other Lipids  Polyunsaturated Fat - A fatty acid with more than one double bond. - Tend to have low melting point because chains bend at double bonds.  Usually liquid at room temperature.  Other Lipids - Terpenes - Steroids - Prostaglandins

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Fats as Food On average, fats yield about 9 kcal of chemical energy per gram, as compared with 4 kcal per gram for carbohydrates.  Animal fats are saturated, while most plant fats are unsaturated. - Can convert oil into solid fat through hydrogenation (adding hydrogen).

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Simple Carbohydrates Carbohydrates are a loosely defined group of molecules that contain carbon, hydrogen, and oxygen in a 1:2:1 ratio.  Monosaccharides (Simple sugars)  Disaccharides - Two monosaccharides joined by a covalent bond.  Polysaccharides - Made of multiple monosaccharide units.

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Simple Carbohydrates Sugar Isomers - Alternative forms of the same chemical formula.  Glucose  Fructose  Galactose

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Linking Sugars Transport Disaccharides  Most organisms transport sugars within their bodies.  Humans - Glucose  Plants - Sucrose

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Linking Sugars Storage Polysaccharides  Organisms store metabolic energy in monosaccharides by converting them into disaccharides. - Maltose - Plant polysaccharides - Starch  Amylose - Animal polysaccharides - Glycogen

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Structural Carbohydrates Glucose can form a ring two ways:  Hydroxyl group attached above or below the plane of the ring. - Below - Alpha - Above - Beta

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Structural Carbohydrates Cellulose - Chain of glucose molecules that consists of all beta-glucose subunits.  Cleavage of subunits requires an enzyme most organisms lack. - Works well as biological structural material. Chitin - Modified form of cellulose with nitrogen group added to the glucose units.  Structural unit in many insects.

Raven - Johnson - Biology: 6th Ed. - All Rights Reserved - McGraw Hill Companies Review Chemistry of Carbon Macromolecules Protein  Amino Acids  Protein Shape Nucleic Acids  DNA and RNA Lipids Carbohydrates

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