ELAINE N. MARIEB EIGHTH EDITION 2 Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings PowerPoint ® Lecture Slide Presentation by Jerry L. Cook, Sam Houston University ESSENTIALS OF HUMAN ANATOMY & PHYSIOLOGY PART A Basic Chemistry

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings  Why do we Study Chemistry?

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Matter and Energy  Matter – anything that occupies space has mass (weight)  Energy – the ability to do work  Chemical Energy- released when bonds are broken (ATP)  Electrical Energy- movement of charged particles  Mechanical Energy- movement of objects (muscles)  Radiant Energy- electromagnetic waves

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Composition of Matter  Elements  Fundamental units of matter  96% of the body is made from four elements  Carbon (C)  Hydrogen (H)  Oxygen (O)  Nitrogen (N)  Atoms  Building Blocks of elements

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Atomic Structure  Nucleus  Protons (p + )  Neutrons (n 0 )  Outside of nucleus  Electrons (e - ) Figure 2.1

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Identifying Elements  Atomic number  Equal to the number of Protons that the atoms contain  Also equal to the number of Electrons  Atomic mass number  Sum of the Protons and Neutrons  Atomic Symbol

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Isotopes and Atomic Weight  Isotopes  Have the same number of Protons  Vary in number of Neutrons Figure 2.3

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Molecules and Compounds  Molecules – two or more atoms combined chemically  Ex: O 2, H 2 O, NaCl, H 2  Compound – two or more different elements combined chemically  Ex: H 2 O, NaCl, C 6 H 12 O 6, OH -, CH 4

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Chemical Reactions  Chemical Reaction – When bonds break, atoms rearrange, and new bonds form.  Atoms are united by chemical bonds  Atoms dissociate from other atoms when chemical bonds are broken  Atoms may rearrange, form new bonds, and make a different new molecule

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Electrons and Bonding  Electrons occupy energy levels called electron 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 fill first

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Electrons and Bonding  Bonding involves interactions between electrons in the outer shell (valence shell)  Full valence shells do not form bonds  Inert Elements (Noble Gases)  Nonreactive

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Inert Elements  Have Complete valence shells and are stable  Shell 1 has 2 electrons  Shell 2 has 8 electrons  Shell 3 has 8 electrons Figure 2.4a

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Reactive Elements  Valence shells are not full and are unstable  Tend to gain, lose, or share electrons  Allows for bond formation, which produces a stable valence Figure 2.4b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Chemical Bonds Ions  Charged particles  Result when atoms gain or lose electrons  Anions are negatively charged  Cations are positively charged  Ionic Bonds  Form when electronsare completely transferred from one atom to another  Opposite charges attract & form ionic bonds IONIC BONDS ANIMATION PRESS TO PLAY

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Chemical Bonds  Covalent Bonds  Atoms become stable through shared electrons  Single covalent bonds share one pair of electrons  Double covalent bonds share two pairs of electrons  Triple covalent bonds share three pairs of electrons Figure 2.6c

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings COVALENT BONDS ANIMATION Examples of Covalent Bonds Figure 2.6a–b PRESS TO PLAY

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.7 Polarity  Covalent bonded molecules  Some are non polar  Electrically neutral as a molecule  Electrons shared equally  Some are Polar  Have a positive and negative side  Electrons shared unequally

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Chemical Bonds  Hydrogen bonds  Weak chemical bonds  Hydrogen is attracted to negative portion of polar molecule  Provides attraction between molecules  Water behaves as a “magnet”, pulling other molecules apart. Thus it is an important solvent.

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Patterns of Chemical Reactions  Synthesis reaction (A+B  AB)  Atoms or molecules combine  Energy is absorbed for bond formation  Endergonic or Anabolic reaction  Growth & Repair. Ex: Amino Acids form proteins, Nucleotides join to form nucleic acids.  Decomposition reaction (AB  A+B)  Molecule is broken down  Chemical energy is released  Exergonic or Catabolic reaction  Digestion. Ex: Glycogen  Glucose

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Synthesis and Decomposition Reactions Figure 2.9a–b

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Figure 2.9c Patterns of Chemical Reactions  Exchange reaction (AB + C  AC+B) (AB + CD  AD + CB)  Involves both synthesis and decomposition reactions  A switch is made between molecule parts and different molecules are made

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Matter  Matter is classified into 2 categories:  Organic  Inorganic

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Biochemistry: Essentials for Life  Organic compounds  Contain Carbon and Hydrogen  Most have strong covalent bonds  Large Molecules  Example: C 6 H 12 O 6 (Glucose)  Inorganic compounds  Lack Carbon  Tend to be simpler & smaller compounds  Example: H 2 O (Water), NaCL (Salt)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Inorganic Compounds  Water  Most abundant inorganic compound  (2/3 rd s of body weight)  Vital properties  High heat capacity  Polarity/Solvent properties  Chemical reactivity  Cushioning

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Inorganic Compounds  Water  High heat capacity:  Prevents temperature changes  Absorbs & transports heat  Polarity/Solvent properties:  Universal solvent  Chemical reactions require water

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Inorganic Compounds  Water  Chemical reactivity:  Hydrolysis- water dissociates & joins larger molecules  Cushioning:  Cerebrospinal fluid- brain, spine  Amniotic fluid- baby  Serous- organs  Synovial- joints  Mucous- membrane linings

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Inorganic Compounds  Salts  Easily dissociate into ions in the presence of water  Ex: NaCl  Na + + Cl -  Vital to many body functions  Electrolytes: (conduct electrical currents) (release ions in water)

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Inorganic Compounds  Acids  Proton donors*Sour  Release Hydrogen ions (H + )*Corrosive  Electrolytes  Bases*Slippery  Proton acceptors*Bitter  Release OH - (Hydroxide), (Electrolytes)  Neutralization reaction  Acids and bases react to form water and a salt  Ex: HCl + NaOH  H 2 O + NaCl

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings pH  Measures relative concentration of hydrogen ions  pH 7 = neutral  pH 0 to < 7 = acid  pH > 7 to 14 = base  Buffers: chemicals that can regulate pH change Figure 2.11

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important 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 © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Organic Compounds  Lipids  Contain carbon, hydrogen, and oxygen  Carbon and hydrogen outnumber oxygen  Insoluble in water LIPIDS ANIMATION PRESS TO PLAY

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Lipids  Common lipids in the human body  Neutral fats (triglycerides)  Found in fat deposits  Composed of fatty acids and glycerol  Source of stored energy  Phospholipids  Form cell membranes  Steroids  Include cholesterol, bile salts, vitamin D, and some hormones

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Organic Compounds  Proteins  Made of amino acids  Contain carbon, oxygen, hydrogen, nitrogen, and sometimes sulfur  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

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings Important Organic Compounds  Nucleic Acids  Provide blueprint of life  Nucleotide bases  A = Adenine  G = Guanine  C = Cytosine  T = Thymine  U = Uracil  Make DNA and RNA

Copyright © 2006 Pearson Education, Inc., publishing as Benjamin Cummings 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