Organic Compounds

Organic Compounds

Carbohydrates Figure 2.12a–b

Figure 2-13 A Starch Section 2-3 Starch Glucose Go to Section:

Carbohydrates Figure 2.12c

Carbohydrates • *Main source of energy for living things • *Plants and some animals also use carbohydrates for structural purposes • *Sugars are stored as starches • *Monomers in starch molecules are sugar molecules

Monosaccharides One sugar carbohydrate C6H12O6 Examples: galactose, glucose. fructose Disaccharides Two sugars C12H22O11 Examples: Sucrose (table sugar composed of glucose and fructose), lactose (milk sugar), maltose Polysaccharides More than two Can be thousands Starch (storage form of sugar) Cellulose (forms cell wall, supporting material in plants,wood and paper) Glycogen (animal starch) *When the level of glucose in your blood runs low, glycogen is released from your liver. The glycogen stored in your muscles supplies energy for contraction and, thus, for movement. Isomers- same molecular formula but different structural formula Example: glucose and fructose

Lipids Figure 2.14a–b

Lipids • Part of cell structures and reserve energy supply: membranes, waterproof coverings • Fats, oils, and waxes (found in fur, skin, leaves, exoskeleton of some insects) • Less O in relation to H • Relatively small, NOT polymers • Long-term energy storage, insulation, protective coating • Furnish about twice as much energy as the same amount of carbohydrates • 7. Fats and oils are chemically similar. Unlike fats, however, oils remain liquid at • room temperature • *Note: Steroids (some are chemical messengers) are also lipids.

Vocabulary • Saturated fat – only single bonds; has the maximum number of hydrogen atoms • (fats with animal origins-milk, beef, butter) • Unsaturated fat– has at least one carbon-carbon double bond • Has double and triple bonds ( fats with plant origins) • Examples – olive oil, corn oil, fish oil, sunflower oil • Polyunsaturated fat– more than one double bond • Fats and cholesterol: • LDL- low density lipoproteins HDL – high density lipoproteins Carry cholesterol to cells (H – Happy, good ) Carry cholesterol away from cells and toward liver for elimination from the body • Lipid derivatives • Phospholipids : Lecithin (part of cell membrane) • Cephalin (brain nerves, neural tissue)

Proteins General structure

Figure 2-16 Amino Acids Section 2-3 Amino group Carboxyl group General structure Alanine Serine Go to Section:

Protein Protein Amino acids Go to Section:

Proteins • Found throughout living organisms - make life possible • Structures are very complex • More than 20 different types of amino acids represent the R (variable) group • There can be more than 3,000 amino acids in a protein • Carbon atoms bond in four places: • A. Amino group (NH2) • B. Carboxyl group (COOH) • C. Hydrogen atom • D. Variable group (R) • This group is a side chain that is different in each amino acid • GLYCINE is the simplest amino acid. Its R group is hydrogen (H).

Proteins form peptide bonds- a bond between C in the carboxyl group of one amino acid and N in the amino group of the next amino acid dipeptide bond – two amino acids linked together by a peptide bond polypeptide chain – a large number of amino acids linked by peptide bonds Polypeptides combine to form proteins. Some proteins control the rate of reactions and regulate cell processes. Some are used to form bones and muscles. Other proteins transport substances into and out of the cells or help to fight disease.

Type Function Examples Hormonal Chemical messengers Glucagon, insulin Transport Transport of other substances Hemoglobin, carrier proteins Structural Physical support Collagen Contractile Movement Actin, myosin Antibodies Defense Immunoglobulins, Interferons Enzymes Biological catalysts Amylase, lipase, ATPase Types of Proteins

Glucagon- secreted by pancreas, helps change glycogen (a polysaccharide that is a major storage product in animals) to glucose (a sugar)Insulin – secreted by pancreas, helps convert glucose to glycogenHemoglobin – an iron-containing protein compound that helps transport O and CO2 (gives blood redcolor)Collagen – part of connective tissue (supports, binds tissue and organs together)Actin – thin filaments found in microfilaments used for cell movement and contraction of muscle cellsMyosin – thick filaments found in muscles Interferons – produced by living cells that have been entered by a virus

Nucleic Acids • Store and transmit hereditary, or genetic information • Largest organic molecules • Nucleic Acids – DNA and RNA • Deoxyribonucleic acid (DNA) contains the sugar deoxyribose. • Ribonucleic acid (RNA) contains the sugar ribose.

Nucleic Acids • Deoxyribonucleic acid (DNA) • Organized by complimentary bases to form double helix • Replicates before cell division • Provides instruction for every protein in the body Figure 2.18c

Nucleic Acids

Enzymes • Catalyst-substance that speeds up the rate of a chemical reaction (lowers the activation energy • Enzymes – proteins that act as catalysts • Cells use enzymes to speed up chemical reactions that take place in cells. • A reaction can take place as much as ten billion times faster. • Very specific • Name derived from the reaction it catalyzes • Lock and key fit (perfect fit)

Enzymes at Work • Carbonic anhydrase – catalyzes the reaction that removes water from carbonic acid • Hexokinase – converts glucose and ATP into glucose-6-phosphate and ADP (stored energy and released energy) • Catalase – one of the fastest acting enzymes; breaks down hydrogen peroxide (poisonous byproduct of most chemical reactions in human cells) into water and oxygen

Commercial Uses of Enzymes • Some enzymes split proteins so they are used in laundry detergents. • Papain, found in papaya, is used in meat tenderizer.

Vocabulary • Substrate – material acted upon by an enzyme; the reactants • Active site – where enzyme and substrate join • Products – substances liberated during the reaction • Coenzyme – non-protein molecule that assists enzyme; vitamins • Denaturation – active sites of enzymes altered; life-threatening • Inhibitor-disables enzyme by joining with it without itself being changed Competitive inhibitor – fake substances (antibiotics) Non-competitive inhibitor – attaches to OR changes the shape of an active site (lead, mercury, cyanide)

Enzyme

Factors Affecting Enzyme Action • pH – Pepsin (stomach) works best at a pH of 1.5-2.2 Trypsin (small intestine) works best at a pH of 7.9-9.0 • Temperature – most at body temperature (37 degrees Celsius) • Relative amounts of enzyme and substrate • Most cells contain proteins that turn key enzymes “on and off” during critical stages in the life of the cell.

Organic Compounds