Essentials of Human Anatomy & Physiology Chapter 2 - Basic Chemistry PDF

Essentials of Human Anatomy & Physiology Seventh Edition Elaine N. Marieb Chapter 2 Basic Chemistry Slides 2.1 – 2.42 Lecture Slides in PowerPoint by Jerry L....

Essentials of Human Anatomy & Physiology Seventh Edition Elaine N. Marieb Chapter 2 Basic Chemistry Slides 2.1 – 2.42 Lecture Slides in PowerPoint by Jerry L. Cook Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  Matter and Energy Matter – anything that occupies space and has mass (weight) Solids, Liquids, Gasses Physical and Chemical changes Energy – the ability to do work Kinetic – when energy is actually doing work Potential – when energy is inactive or stored Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.2  Matter and Energy Forms of Energy Chemical – stored in the bonds of chemical substances Electrical – results from the movement of charged particles - ions Mechanical – directly involved in moving matter - muscles Radiant – travels in waves – the electromagnetic spectrum including X-rays, infrared, light, radio, and UV rays Can easily be converted from 1 form to another but is not 100% efficient – some lost as heat Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.3  Composition of Matter Elements Fundamental units of matter – cannot be broken down into smaller units 96% of the body is made from four elements Carbon (C) Oxygen (O) Hydrogen (H) Nitrogen (N) Atoms Building blocks of elements Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.4  Atomic Structure Inside the nucleus Protons (p+) Neutrons (n0) Outside the nucleus Electrons (e-) Figure 2.1 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.5  Identifying Elements Atomic number Equal to the number of protons that the atoms contain – also equals number of electrons Atomic mass number Sum of the protons and neutrons Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.6  Atomic Weight and Isotopes Isotopes Have the same number of protons and electrons so same atomic number Vary in number of neutrons so different atomic masses Atomic weight Close to mass number of most abundant isotope Atomic weight reflects natural isotope variation Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.7  Radioactivity Radioisotope Heavy isotope Tends to be unstable Decomposes to more stable isotope Radioactivity Process of spontaneous atomic decay Releases particles – alpha, beta, and gamma rays Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.8  Molecules and Compounds Molecule – two or more atoms combined chemically Compound – two or more different atoms combined chemically Compounds have properties different from the properties of the atoms they are made of Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.9  Chemical Reactions Chemical reactions occur when atoms combine or dissociate from other atoms Atoms are united by chemical bonds Atoms dissociate from other atoms when chemical bonds are broken Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.10  Electrons and Bonding Electrons occupy energy levels called electron levels or shells Electrons closest to the nucleus are most strongly attracted Each shell has distinct properties Number of electrons has an upper limit Shells closest to nucleus usually fill first Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.11  Electrons and Bonding Bonding involves interactions between electrons in the outer shell (the valence shell) Full valence shells do not form bonds Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.12  Inert Elements Have complete valence shells and are stable Rule of 8s Shell 1 has 2 electrons Shell 2 has 10 electrons 10 = 2 + 8 Shell 3 has 18 electrons Figure 2.4a 18 = 2 + 8 + 8 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.13  Reactive Elements Valence shells are not full and are unstable Tend to gain, lose, or share electrons Allows for bond formation, which produces stable valence Figure 2.4b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.14  Chemical Bonds Ionic Bonds Form when electrons are completely transferred from one atom to another Ions Charged particles Either donate or accept electrons Anions are negative – have accepted Cations are positive – have donated Opposites attract so stick together – most form salts Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.15  Chemical Bonds Covalent Bonds Atoms become stable through shared electrons Single covalent bonds share one electron Double covalent bonds share two electrons Figure 2.6c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.16  Examples of Covalent Bonds Figure 2.6a, b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.17  Polarity Covalent bonded molecules Some are non-polar Electrically neutral as a molecule Some are polar Have a positive and negative side Polar molecules orient Figure 2.7 themselves toward other polar or charged particles Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.18  Chemical Bonds Hydrogen bonds Weak chemical bonds Hydrogen is attracted to negative portion of polar molecule Provides attraction between molecules Surface tension – bonds between water molecules Intramolecular bonds – binding of different parts of the same molecule to form a 3D shape such as proteins Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.19  Patterns of Chemical Reactions Synthesis reaction (A+BAB) Atoms or molecules combine Energy is absorbed for bond formation Anabolic activities – constructive activities Decomposition reaction (ABA+B) Molecule is broken down Chemical energy is released when bonds are broken Catabolic processes – decomposition activities Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.20  Synthesis and Decomposition Reactions Figure 2.9a, b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.21  Patterns of Chemical Reactions Exchange reaction (AB+CAC+B) Involves both synthesis and decomposition reactions Switch is made between molecule parts and different molecules are made Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.22  Biochemistry: Essentials for Life Organic compounds Contain carbon Most are covalently bonded Example: C6H12O6 (glucose) Inorganic compounds Lack carbon Tend to be simpler compounds Example: H2O (water) Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.23  Important Inorganic Compounds Water Most abundant inorganic compounds Vital properties High heat capacity Polarity/solvent properties Solute, Solvent, Mixture, Solution, Suspension, Colloid Chemical reactivity hydrolysis reactions Cushioning Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.24  Important Inorganic Compounds Salts Easily dissociate into ions in the presence of polar water molecules Vital to many body functions Include electrolytes, which conduct electrical currents in solution Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.25  Important Inorganic Compounds Like salts, acids and bases are electrolytes Acids – H+ Can release detectable hydrogen ions Sour taste and can “burn” Proton donors Bases – OH- Bitter taste, slippery Proton acceptors Neutralization reaction Acids and bases react to form water and a salt Slide 2.26 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings  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 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.27  Important Organic Compounds Carbohydrates Contain carbon, hydrogen, and oxygen in a 1:2:1 ratio Include sugars and starches Classified according to size Monosaccharides – simple sugars Disaccharides – two simple sugars joined by dehydration synthesis – H2O is lost Polysaccharides – long branching chains of linked simple sugars Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.28  Carbohydrates Provide a ready, easily used source of food energy for cells Figure 2.12a, b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.29  Carbohydrates Figure 2.12c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.30  Important Organic Compounds Lipids Contain carbon, hydrogen, and oxygen Carbon and hydrogen outnumber oxygen Insoluble in water but soluble in other lipids “Like dissolves like” Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.31  Important Organic Compounds Common lipids in the human body Neutral fats (triglycerides) Found in fat deposits Composed of fatty acids and glycerol Solid (animal fats) or liquid (plant fats) Saturated – animal fats or unsaturated – plant fats Source of stored energy Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.32  Important Organic Compounds Common lipids in the human body (continued) Phospholipids Form cell membranes – polar properties Steroids Four interlocking rings Fat-soluble Include cholesterol, bile salts, vitamin D, and some hormones Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.33  Lipids Figure 2.14a, b Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.34  Cholesterol Figure 2.14c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.35  Important Organic Compounds Proteins Made of strings of the 20 amino acids Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur Amino acids have three main parts Amine group – gives basic properties Acid group – allows them to act as acids R-group – variable Strung together with peptide bonds to make polypeptides (proteins) Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.36  Important Organic Compounds Account for over half of the body’s organic matter Provides for construction materials for body tissues Plays a vital role in cell function Act as enzymes, hormones, and antibodies Classified in two divisions Fibrous (structural) proteins Globular (functional) proteins Can be denatured by heat, pH changes – changes the active site (structure and function) Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.37  Enzymes Act as biological catalysts – names end in ase Increase the rate of chemical reactions by lowering the level of activation energy required for the reaction Do not get changed by the reactions they work with Can be used multiple times – only need small amounts Determine which reactions can take place – enzyme must be present for reaction to occur Specific for their individual job Figure 2.16 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.38  Enzymes Structure of enzyme (really a protein) must be correct before it can bind to the substrate – structure and function Just like proteins, can be denatured by heat or changes in pH Can be activated or deactivated according to bodies need for the enzyme Figure 2.16 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.39  Important Organic Compounds Nucleic Acids Nucleotides – 3 parts Provide blueprint of life Nitrogen-containing base Nucleotide bases A pentose sugar – A = Adenine either deoxyribose or G = Guanine ribose A phosphate group C = Cytosine T = Thymine U = Uracil Make DNA and RNA Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.40  Important Organic Compounds Deoxyribonucleic acid (DNA) Organized by complimentary bases to form double helix Replicates before cell division Provides instruction for every protein in the body Figure 2.17c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.41  Important Organic Compounds Ribonucleic acid (RNA) Single stranded Three types mRNA, tRNA, rRNA Used in protein synthesis Figure 2.17c Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.42  Important Organic Compounds Adenosine triphosphate (ATP) Chemical energy used by all cells Energy is released by breaking high energy phosphate bond ATP is replenished by oxidation of food fuels Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.43  Adenosine Triphosphate (ATP) Modified nucleotide Adenine base Ribose sugar Three phosphate groups – attached by unique chemical bonds called high-energy phosphate bonds ATP  ADP + P + E Figure 2.18a Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.44  How ATP Drives Cellular Work Figure 2.19 Copyright © 2003 Pearson Education, Inc. publishing as Benjamin Cummings Slide 2.45