Anatomy and Physiology by Rod R Seeley 6th edition chapter 2 power-point

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Anatomy and Physiology, Sixth Edition
Rod R. SeeleyIdaho State University Trent D.
StephensIdaho State University Philip
TatePhoenix College
Chapter 02 Lecture Outline
See PowerPoint Image Slides for all figures and
tables pre-inserted into PowerPoint without notes.
Copyright The McGraw-Hill Companies, Inc.
Permission required for reproduction or display.
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Chapter 2

• The Chemical Basis of Life

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Basic Chemistry

• Matter, Mass, and Weight
• Matter Anything that occupies space and has mass
• Mass The amount of matter in an object
• Weight The gravitational force acting on an
  object of a given mass
• Elements and Atoms
• Elements The simplest type of matter with unique
  chemical properties
• Atoms Smallest particle of an element that has
  chemical characteristics of that element

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Atomic Structure

• Atoms composed of subatomic particles
• Neutrons no electrical charge
• Protons positive charge
• Electrons negative charge
• Nucleus
• Formed by protons and neutrons
• Most of volume of atom occupied by electrons

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Atomic Number and Mass Number

• Atomic Number Equal to number of protons in each
  atom which equals the number of electrons
• Mass Number Number of protons plus number of
  neutrons

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Isotopes and Atomic Mass

• Isotopes Two or more forms of same element with
  same number of protons and electrons but
  different neutron number
• 3 types of hydrogen
• Denoted by using symbol of element preceded by
  mass number as 1H, 2H, 3H
• Atomic Mass Average mass of naturally occurring
  isotopes

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Electrons and Chemical Bonding

• Ion When an atom loses or gains electrons and
  become charged
• Cation Positively charged ion
• Anion Negatively charged ion
• Ionic Bonding
• Cations and anions are attracted to each other

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Covalent Bonding

• Atoms share one or more pairs of electrons
• Single covalent Electron pair between 2 atoms
• Double covalent Two atoms share 4 electrons
• Nonpolar covalent Electrons shared equally
• Polar covalent Electrons not shared equally

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Molecules and Compounds

• Molecules Two or more atoms chemically combine
  to form and independent unit
• Example Water
• Compounds A substance composed of two or more
  different types if atoms chemically combined
• Example Hydrogen Molecule
• Molecular Mass Determined by adding up atomic
  masses of its atoms or ions
• Example NaCl (22.99 35.45)

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Intermolecular Forces

• Result from weak electrostatic attractions
  between oppositely charged parts or molecules, or
  between ions and molecules
• Weaker than forces producing chemical bonding

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Intermolecular Forces

• Hydrogen Bonds
• Water Positively charged hydrogen atoms bond
  with negatively charged oxygen atoms of other
  water molecules
• Important role in determining shape of complex
  molecules

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Intermolecular Forces

• Solubility Ability of one substance to dissolve
  in another
• Example Sugar dissolves in water
• Dissociation or Separation
• Ionic compounds
• Cations are attracted to negative end and anions
  attracted to positive end of water molecules

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Intermolecular Forces

• Electrolytes Cations () and anions (-) that
  dissociate in water
• Capacity to conduct an electric current
• Currents can be detected by electrodes
• Nonelectrolytes Molecules that do not dissociate
  form solutions that do not conduct electricity

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Chemical Reactions

• Chemical Reactions Atoms, ions, molecules or
  compounds interact to form or break chemical
  bonds
• Metabolism All anabolic and catabolic reactions
  in the body
• Catabolism Decomposition reactions
• Hydrolysis Reactions that use water
• Anabolism Growth, maintenance, and repair of
  the body in synthesis reactions
• Produce molecules characteristic of life ATP,
  proteins, carbohydrates, lipids, and nucleic acids

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Synthesis and Decomposition Reactions

• Synthesis Reactions
• Two or more reactants chemically combine to form
  a larger product
• Anabolism All bodys synthesis reactions
• Decomposition Reactions
• Reverse of synthesis reactions
• Catabolism Reactions of decomposition in body

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Oxidation-Reduction Reactions

• Oxidation
• Loss of an electron by an atom
• Reduction
• Gain of an electron by an atom
• Oxidation-Reduction Reactions
• The complete or partial loss of an electron by
  one atom is accompanied by the gain of that
  electron by another atom

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Speed of Chemical Reactions

• Activation Energy Minimum energy reactants must
  have to start a chemical reaction
• Catalysts Substances that increase the rate of
  chemical reactions without being permanently
  changed or depleted
• Enzymes Increase the rate of chemical reactions
  by lowering the activation energy necessary for
  reaction to begin

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Water

• Inorganic
• Stabilizes body temperature
• Protection
• Necessary for many chemical reactions of life
• Mixing Medium
• Mixture Substance physically but not chemically
  combined
• Solution Liquid, gas, or solid uniformly
  distributed
• Solvent What dissolves the solute
• Solute What is to be dissolved

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Acids and Bases Salts and Buffers

• Acid A proton donor or any substance that
  releases hydrogen ions
• Bases A proton acceptor or any substance that
  binds to or accepts hydrogen ions
• Salts A cation consisting of other than a
  hydrogen ion and other than an anion or hydroxide
  ion
• Buffers A solution of a conjugate acid-base pair
  in which acid and base component occur in similar
  concentrations

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The pH Scale

• Refers to the Hydrogen ion concentration in a
  solution
• Neutral pH of 7 or equal hydrogen and hydroxide
  ions
• Acidic a greater concentration of hydrogen ions
• Alkaline or basic a greater concentration of
  hydroxide ions

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Organic Chemistry

• Carbohydrates
• Composed of carbon, hydrogen, oxygen
• Lipids
• Composed mostly of carbon, hydrogen, oxygen
• Proteins
• Composed of carbon, hydrogen, oxygen,nitrogen
• Nucleic Acids DNA and RNA
• Composed of carbon, hydrogen, oxygen, nitrogen,
  phosphorus
• Adenosine Triphosphate (ATP)
• Composed of adenosine and three phosphate groups

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Carbohydrates

• Monosaccharides
• Simple sugars glucose, fructose, galactose
• Disaccharides
• Two simple sugars bound together by dehydration
  sucrose, lactose, maltose
• Polysaccharides
• Long chains of many monosaccharides glycogen in
  animals starch and cellulose in plants

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Lipids

• Lipids Can be dissolved in nonpolar organic
  solvents as alcohol or acetone but relatively
  insoluble in water
• Fats Ingested and broken down by hydrolysis
• Triglycerides composed of glycerol and fatty
  acids
• Phospholipids Important structural component of
  cell membranes
• - Steroids Cholesterol, bile salts, estrogen,
  testosterone

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Proteins

• Amino acids The building blocks of protein
• Peptide bonds Covalent bonds formed between
  amino acids during protein synthesis
• Enzymes Protein catalysts

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Nucleic Acids DNA and RNA

• DNA Deoxyribonucleic acid
• Genetic material of cells copied from one
  generation to next
• Composed of 2 strands of nucleotides
• Each nucleotide contains one of the organic bases
  of adenine or guanine which are purines and
  thymine or cystosine which are pyrimidines
• RNA Ribonucleic acid
• Similar to a single strand of DNA
• Four different nucleotides make up organic bases
  except thymine is replaced with uracil
  (pyrimidine)

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Adenosine Triphosphate (ATP)

• Energy currency of the body
• Provides energy for other chemical reactions as
  anabolism or drive cell processes as muscle
  contraction
• All energy-requiring chemical reactions stop when
  there is inadequate ATP