Transcript Slides 2.21
Essentials of Human Anatomy & Physiology Seventh Edition Elaine N. Marieb Chapter 2 Basic Chemistry Slides 2.21 – 2.40 Patterns of Chemical Reactions • Synthesis reaction (A+BAB) • Atoms or molecules combine • Energy is absorbed for bond formation • Decomposition reaction (ABA+B) • Molecule is broken down • Chemical energy is released Slide 2.18 Synthesis and Decomposition Reactions Figure 2.9a, b Slide 2.19 Patterns of Chemical Reactions • Exchange reaction (AB + CAC+B) • Bonds are made and broken • Switch is made between molecule parts and different molecules are made Slide 2.20 Biochemistry: The Chemical Composition of Living Matter • Organic compounds • Contain carbon • Example: C6H12O6 (glucose) • Inorganic compounds • Lack carbon • Usually simpler • Example: H2O (water) Slide 2.21 Important Inorganic Compounds • Water • Most abundant inorganic compound • Vital properties • High heat capacity •Absorbs and releases large amounts of heat before the temp changes greatly • Polarity/solvent properties •Great solvent, because of polarity it can dissolve many substances. Slide 2.22 Important Inorganic Compounds • Chemical reactivity •Helps with hydrolysis and dehydration synthesis reactions • Cushioning •Cerebrospinal fluid protects the brain and spinal cord Slide 2.22 Important Inorganic Compounds • Salts • Become ions in the presence of water • Na+Cl- (table salt) Ca+Cl- (in bones) Slide 2.23 Important Inorganic Compounds • Characteristics of Acids • ↑H+ and ↓OH• Ex: gastric juice, lemon juice • 0 to 6 on pH scale • Characteristics of Bases • ↓H+ and ↑OH• Blood, seawater, ammonia • 8 to 14 on pH scale Slide 2.24 pH • Measures relative concentration of hydrogen ions • pH 7 = neutral • pH below 7 = acidic • pH above 7 = basic • Buffers • Chemicals that can regulate pH change Figure 2.11 Slide 2.25 Organic Compounds • Carbohydrates • Contain carbon, hydrogen, and oxygen • Include sugars and starches • Classified according to size • Monosaccharides – simple sugars • Disaccharides – two simple sugars joined by dehydration synthesis • Polysaccharides – long branching chains of linked simple sugars Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.26 Carbohydrates Figure 2.12a, b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.27 Carbohydrates Figure 2.12c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.28 Dehydration Synthesis • Monomers are built up into polymers. • Water is taken away and the synthesis of molecules occurs Dehydration Synthesis Hydrolysis • Polymers are broken down into monomers. • Water is added and the lysis of the polymer occurs. Hydrolysis Organic Compounds • Dehydration Synthesis and Hydrolysis of a molecule of sucrose. • If glucose is not immediately need for ATP synthesis then it will be converted to fats and stored. Important Organic Compounds • Lipids (aka- fats) • Enter the body from- meats, egg yolks, milks, oils (animal or plant) • In the body as neutral fats, phospholipids, and steroids • Carbon and hydrogen outnumber oxygen • Example: Tristearin- C57 H110 O6 Slide 2.29 Important Organic Compounds • Most lipids are insoluble in water • With the exception of phospholipids which are found in cell membranes. Organic Compounds • Neutral Fats or Triglycerides • Composed of- 3 fatty acids and a glycerol • Results in E-shaped molecule • Glycerol backbone is the same in all triglycerides, the fatty acids will differ. Organic Compounds • Saturated- carbons single bond • Unsaturated- carbons double or triple bond Organic Compounds • Neutral fats- yield large amounts of energy in the form of ATP • Fat deposits around organs and body help prevent heat loss and give cushioning. Phospholipids • Hydrophobic tails (non polar) which means that it hates water • Hydrophilic head (polar) which means it like water. • Cell membranes are made of a phospholipid bilayer. Lipids Figure 2.14a, b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.31 Steroids and Cholesterol •Most important steroid is cholesterol •It is used to form vitamin D, sex hormones, cortisol, and bile salts. Figure 2.14c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Important Organic Compounds • Proteins • Make up 50% of organic matter in the body • Have varied functions Slide 2.33a Important Organic Compounds • Amino Acids- the building blocks of proteins • Have amine group (base) nitrogen • Have acid group • Amino Acids join together to form chains and create a functional protein. Slide 2.33b Fibrous Proteins • Strand-like, structural proteins • Examples: collagen, cartilage, keratin Slide 2.33b Globular Proteins • Spherical molecules • They do things rather than just provide structure • Also called functional proteins • 3-D structure is held in place by hydrogen bonds • Function depends on active sites on the surface that interact chemically with other molecules Enzymes • Functional proteins that act as biological catalysts • Increase the rate of chemical reactions Figure 2.16 Enzymes • Without enzymes biological reactions would not occur • Examples- • Hydrolase- adds water • Oxidase- causes oxidation • Enzyme names always end in –ase Figure 2.16 Important Organic Compounds • Nucleic Acids • Provide blueprint of life • Composed of C, O, H, N, P • The building blocks of nucleic acids are nucleotides • Nitrogen containing base varies • 5-carbon sugar is same • Phosphate group is same Slide 2.35 Important Organic Compounds • There are 5 kinds of nucleotides • A = Adenine • G = Guanine • C = Cytosine • T = Thymine • U = Uracil • DNA- deoxyribonucleic acid • RNA- ribonucleic acid • DNA has- A,T,C,G Important Organic Compounds • ATP- Adenosine triphosphate • Chemical energy used by all cells • Energy is released by breaking high energy phosphate bond • ATP is replenished by oxidation of food fuels • ATP ↔ ADP + P + Energy Slide 2.37 Adenosine Triphosphate (ATP) Figure 2.18a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.38 How ATP Drives Cellular Work Figure 2.19 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.39