Anatomy and Physiology Reviewer PDF

CHAPTER 1 -Study of different species to learn about Major Themes of Anatomy and Physiology bodily function Animal surgery Anatomy and physiology (A&P)...

CHAPTER 1 -Study of different species to learn about Major Themes of Anatomy and Physiology bodily function Animal surgery Anatomy and physiology (A&P) Animal drug tests -Is about human structure and function-the -Basis for the development of new drugs and biology of the human body medical procedures. How our body works Greek and Roman Legacy -A&P is a foundation for advanced study in Physicians in Mesopotamia and Egypt health care, exercise physiology, pathophysiology, and -3,000 years ago used herbal drugs, salts, and other health-care-related fields physical therapy -Considers the historical development and a central concept of physiology-homeostasis Hippocrates (Greek Physician) -"Father of medicine" Anatomy -Established a code of ethics (Hippocratic - Study of the Human body Oath) -Urged physicians to seek natural causes of Examining structure of the Human Body: disease rather than attributing them to acts of the gods and demons -Inspection -Palpation Aristotle -Auscultation -One of the first philosophers to write about -Percussion anatomy and physiology -Believed that diseases had either supernatural Cadaver dissection causes or physical causes -Called supernatural causes of disease -Study of more than one species in order to theologi examine structural similarities and differences and -Called natural causes for disease physiologi analyze evolutionary trends -This gave rise to the terms physician and physiology Exploratory surgery -Believed that complex structures are built -Open body and take a look inside from simpler parts Medical imaging Claudius Galen -Viewing of the inside of the body without -Physician to the Roman gladiators surgery -Did animal dissections since use of cadavers Radiology was banned in his time -branch of medicine concerned with imaging -Saw science as a method of discover, not just Gross Anatomy a body of facts taken on faith -Study of structures that can be seen by the -Wrote book advising followers to trust their naked eye own observation more than the teaching of dogma of the "ancient masters" Gross anatomy -Study of structures that can be seen with the naked eye The Birth of Modern Medicine Cytology Christian culture of Europe in Middle Ages -Study of structure and function of cells -Science severely repressed Histology (microscopic anatomy) -Taught medicine primarily as dogmatic -Examination of cells with microscope commentary on Galen and Aristotle Ultrastructure -Crude medical illustrations -View molecular detail under electron microscope In Jewish and Muslim cultures free inquiry was less Histopathology inhibited -Microscopic examination of tissues for signs of disease Jewish physician Maimonides (Moses ben Maimon) Physiology - The Study of Function -Wrote 10 influential medical texts Subdisciplines -Was physician to Egyptian sultan, Saladin -Neurophysiology (physiology of nervous system) Avicenna (Ibn Sina) from Muslim world -Endocrinology (physiology of hormones) -"The Galen of Islam" -Pathophysiology (mechanisms of disease) -Combined Galen and Aristotle findings with Comparative physiology original -discoveries -Limitations on human experimentation  -Wrote The Canon of Medicine, used in -All functions of the body are interpreted as medical schools for 500 years effects of cellular activity Andreas Vesalius Scientific Method -Taught anatomy in Italy Francis Bacon, in England, and René Descartes, in -Catholic Church relaxed restrictions on France dissection of cadavers and permitting autopsies -Philosophers who invented new habits of Barbering and surgery were considered "kindred arts scientific thought of the knife" -Sought systematic way of seeking similarities, -Performed his own dissections rather than the differences, and trends in nature and drawing useful barber-surgeons generalizations from observable facts -Published first atlas of anatomy, De Humani Corporis Fabrica (On the Structure Body) in 1543 Governments of England and France -Established academies of science that still William Harvey exist today -Early physiologist-contributions represent the birth of experimental physiology Science and scientific methods -Remembered for early studies on blood -Set standards for truth circulation -Realized blood flows out from heart and back The Inductive Method to it again Described by Francis Bacon -Published book De Motu Cordis (On the -Making numerous observations until one Motion of the Heart) in 1628 becomes confident in drawing generalizations and predictions from them Michael Servetus -Knowledge of anatomy obtained by this -Along with Harvey, they were the first Western method scientists to realize that blood must circulate continuously around the body, from the heart to other Proof in science organs, and back to the heart again -Reliable observations -Tested and confirmed repeatedly Robert Hooke -Not falsified by any credible observation -Made many improvements to the compound microscope- two lenses: ocular lens (eyepiece) and In science, all truth is tentative objective lens (near specimen) -"Proof beyond a reasonable doubt" Invented specimen stage, illuminator, coarse and fine focus controls His microscopes magnified only 30X The Hypothetico-Deductive Method First to see and name "cells" -More physiological knowledge gained by this -Published first comprehensive book of method microscopy (Micrographia) in 1665 -Investigator asks a question -Formulates a hypothesis -an educated Antony van Leeuwenhoek speculation or possible answer to the question -Invented a simple (single-lens) microscope -Characteristics of a good hypothesis with great magnification to look at fabrics (200X) -Consistent with what is already known -Published his observations of blood, lake -Testable and possibly falsifiable with water, sperm, bacteria from tooth scrapings, and many evidence other things Falsifiability Carl Zeiss and Ernst Abbe -if we claim something is scientifically true, we -Greatly improved compound microscopes must be able to specify what evidence it would take to Added condenser and superior optics prove it wrong Eliminated blurry edges (spherical aberration) Hypothesis and rainbowlike distortions (chromatic -to suggest a method for answering questions: aberration) written as "if-then" statements Matthias Schleiden and Theodor Schwann Experimental Design -With improved microscopes, examination of a Sample size wide variety of specimens followed -Number of subjects used in a study -Concluded that "all organisms were -Controls for chance events and individual composed of cells" variation -First tenet of cell theory -Considered as the most important Controls breakthrough in biomedical history -Control group and treatment group  -Comparison of treated and untreated Development of bacterial resistance to individuals antibiotics Appearance of new strains of AIDS virus Psychosomatic effects -Effects of the subject's state of mind on his or Natural selection her physiology -Some individuals within a species have -Use of placebo in control group hereditary advantage over their competitors Better camouflage Experimenter bias Disease resistance -Prevented with double-blind study Ability to attract mates Selection Pressures Statistical testing -natural forces that promote the reproductive -Provides statements of probability success of some individuals more than others -Difference between control and test subjects was not random variation Adaptations -Results due to the variable being tested -features of an organism's anatomy, physiology, or behavior that have evolved in response Peer Review to these selection pressures and enable the organism Critical evaluation by other experts in the field to cope with the challenges of its environment -Done prior to funding or publication Model -animal species selected for -Done by using verification and repeatability of research on a particular problem results Closest relative: chimpanzee Facts, Laws, and Theories -Difference of only 1.6% in DNA structure Scientific fact -Chimpanzees and gorillas differ by 2.3% -Information that can be independently verified by a trained person Study of evolutionary relationships -Help us chose animals for biomedical Law of nature research (the animal model) -Generalization about the predictable way -Rats and mice used extensively due to issues matter and energy behave involved with using chimpanzees -Results from inductive reasoning and repeated observations Vestiges of Human Evolution -Written as verbal statements or mathematical Vestigial organs formulae -remnants of organs that apparently were better developed and more functional in the ancestors Theory of a species, and now serve little or no purpose -An explanatory statement or set of Piloerector muscle (for goose bumps) statements derived from facts, laws, and confirmed Auricularis muscles (ears) hypotheses Summarizes what we know Our Basic Primate Adaptations Suggests direction for further study Primates -order of mammals to which humans, Human Origins and Adaptations monkeys, and apes belong Charles Darwin -On the Origin of Species by Means of Natural Earliest primates Selection (1859) "the book that shook the world" -Squirrel-sized, arboreal, insect-eating African -The Descent of Man (1871)-human evolution, mammals anatomy and behavior, relationship to other animals -Moved to trees due to safety, food supply, and lack of competition Theory of natural selection -How species originate and change through Adaptations for arboreal (treetop) lifestyle time -Mobile shoulders -Changed prevailing view of our origin, nature -Opposable thumbs made hands prehensile to and our place in the universe grasp branches and encircle them with the thumb and -Increases understanding of human form and finger function -Forward-facing eyes (stereoscopic vision) Depth perception for leaping and Evolution, Selection, and Adaptation catching prey Evolution Color vision -Change in genetic composition of population -Distinguish ripe fruit and young, less of organisms toxic foliage Larger brains and good memory  -Remember food sources and improved social organization Walking Upright African forest became grassland 4 to 5 million years ago - Producing more predators and less protection Bipedalism -standing and walking on two legs -Helps spot predators, carry food or infants Adaptations for bipedalism Characteristics of Life -Skeletal and muscular modifications Organization -Increased brain volume -living things exhibit a higher level of -Family life and social changes organization than nonliving things Other Homo species Cellular composition -discovered recently still matter of -living matter is always compartmentalized considerable debate into one or more cells Homo sapiens Metabolism -originated in Africa 200,000 years ago -sum of all internal chemical change: -Sole surviving hominid species anabolism (synthesis) and catabolism (digestion) Evolutionary (darwinian) medicine Responsiveness and movement -traces some of our diseases and -sense and react to stimuli (responsiveness imperfections to our past irritability and excitability) The Hierarchy of Complexity Homeostasis Organism composed of organ systems -maintaining relatively stable internal conditions Organ systems composed of organs Development Organs composed of tissues -differentiation and growth Tissues composed of cells Reproduction -producing copies of themselves; pass genes Cells composed of organelles to offspring Organelles composed of molecules Evolution -mutations: changes in genetic structure Molecules composed of atoms Physiological Variation Anatomical Variation -Sex, age, diet, weight, physical activity No two humans are exactly alike Typical physiological values -70% most common structure Reference man -30% anatomically variant -22 years old, 154 lb, light physical activity -Variable number of organs -Consumes 2,800 kcal/day Missing muscles, extra vertebrae, renal Reference woman arteries -Same as man except 128 lb and Variation in organ locations (situs solitus, situs 2,000 kcal/day inversus, dextrocardia, situs perversus) Failure to consider variation can lead to overmedication of elderly or medicating women on the basis of research done on men Homeostasis and Negative Feedback Homeostasis -the body's ability to detect change, activate mechanisms that oppose it, and thereby maintain relatively stable internal conditions  -if too warm, vessels dilate (vasodilation) in Claude Bernard (1813-78) the skin and sweating begins (heat-losing mechanism) -Constant internal conditions regardless of -If too cold, vessels in the skin constrict external conditions (vasoconstriction) and shivering begins (heat-gaining Internal body temperature ranges from mechanism) 97°-99°F despite variations in external temperature Homeostasis and Negative Walter Cannon (1871-1945) Feedback -Coined the term homeostasis -Sitting up in bed causes a drop in blood -State of the body fluctuates (dynamic pressure in the head and upper torso region (local equilibrium) within limited range around a set point imbalance in homeostasis); detected by baroreceptors -Negative feedback keeps variable close to the set point Baroreceptors Loss of homeostatic control causes illness or -(sensory nerve endings) in the arteries near death the heart alert the cardiac center in the brainstem. They transmit to the cardiac center Negative Feedback Loop -Cardiac center sends nerve signals that -Body senses a change and activates increase the heart rate and return the blood pressure mechanisms to reverse it- dynamic equilibrium to normal; regulates heart rate -Because feedback mechanisms alter the -Failure of this to feedback loop may produce original changes that triggered them (temperature, for dizziness in the elderly example), they are called feedback loops Receptor -senses change in the body (e.g., stretch receptors that monitor blood pressure) Integrating (control) center -control center that processes the sensory information, "makes a decision," and directs the response (e.g., cardiac center of the brain) Effector -carries out the final corrective action to restore homeostasis (e.g., cell or organ) Example: Room temperature does not stay at set point of 68°F-it only averages 68°F Positive Feedback and Rapid Change Self-amplifying cycle -Leads to greater change in the same direction -Feedback loop is repeated-change produces more change Normal way of producing rapid changes -Occurs with childbirth, blood clotting, protein digestion, fever, and generation of nerve signals Example: Brain senses change in blood temperature  The Importance of Precision -Be precise in your terms -Spell correctly -Health-care professions demand the same type of precision -People's lives will be in your hands Review of Major Themes Cell theory -All structure and function result from the activity of cells Homeostasis -The purpose of most normal physiology is to maintain stable conditions within the body Evolution -The human body is a product of evolution Fever > 104°F -Metabolic rate increases Hierarchy of structure -Body produces heat even faster -Human structure can be viewed as a series of -Body temperature continues to rise levels of complexity -Further increasing metabolic rate -Cycle continues to reinforce itself Unity of form and function -Becomes fatal at 113°F -Form and function complement each other; physiology cannot be divorced from anatomy The History of Anatomical Terminology Standard international anatomical terminology Terminologia Anatomica (TA) -was codified in 1998 by professional associations of anatomists About 90% of medical terms from 1,200 Greek and Latin roots Analyzing Medical Terms Terminology based on word elements -Lexicon of 400 word elements on the inside back cover of textbook Scientific terms -One root (stem) with core meaning Terms of Direction -Combining vowels join roots into a word Superior - above -Prefix modifies core meaning of root word Inferior - below -Suffix modifies core meaning of root word Medial - to the middle Lateral - to the side Anterior/Ventral – in front Posterior/Dorsal - behind Cephalad/Craniad - going to the head Caudad - going to the tail Anatomical Plane  -Slice-type image -Superior quality to CT scan -Best for soft tissue -Mechanics Alignment and realignment of hydrogen atoms with magnetic field and radio waves Varying levels of energy given off used by computer to produce an image Sonography -Second oldest and second most widely used -Mechanics High-frequency sound waves echo back from internal organs -High-frequency sound waves echo back from internal organs Sagittal Plane Obstetrics -divides the left and right Image not very sharp Coronal Plane (frontal) -division of posterior and Anterior Anatomical Cavities Transverse Plane -divides the superior and anterior Medical Imaging Radiography (X-rays) -William Roentgen's discovery in 1885 -Penetrate tissues to darken photographic film beneath the body -Dense tissue appears white -Over half of all medical imaging -Until 1960s, it was the only method widely available Radiopaque substances -Injected or swallowed -Fills hollow structures Blood vessels Intestinal tract Computed tomography (CT scan) -Formerly called a CAT scan -Low-intensity X-rays and computer analysis Slice-type image Increased sharpness of image Medical Imaging-Nuclear Medicine Positron emission tomography (PET) scan -Assesses metabolic state of tissue -Distinguished tissues most active at a given moment -Mechanics-inject radioactively labeled glucose Positrons and electrons collide Gamma rays given off Detected by sensor Analyzed by computer Image color shows tissues using the most glucose at that moment Damaged tissues appear dark Magnetic resonance imaging (MRI) CHAPTER 2 -Atomic Mass of an element is approximately The Chemistry of Life equal to its total number of protons and neutrons -Atoms, lons and Molecules -Water and Mixtures Electrons - in concentric clouds that surround the -Energy and Chemical Reactions nucleus -Organic Compounds -electron: single negative charge, very low mass -determine the chemical properties of an atom Atoms, Ions and Molecules -the atom is electrically neutral because Biochemistry number of electrons is equal to the number of protons -the study of the molecules that compose -valence electrons in the outermost shell living organisms -determine chemical bonding properties of an -carbohydrates atom -fats -proteins Isotopes and Radioactivity -nucleic acids Isotopes -The chemical elements -varieties of an element that differ from one -Atomic structure another only in the number of neutrons and therefore -Isotopes and radioactivity in atomic mass -Ions, electrolytes and free radicals -extra neutrons increase atomic weight -Molecules and chemical bonds -isotopes of an element are chemically similar -have same valence electrons The Chemical Elements Element Atomic weight -simplest form of matter to have unique -of an element accounts for the fact that an chemical properties element is a mixture of isotopes Atomic number -number of protons in its nucleus Radioisotopes and Radioactivity -periodic table Isotopes Elements arranged by atomic number -same chemical behavior, differ in physical Elements represented by one- or two letter behavior symbols -breakdown (decay) to more stable isotope by -24 elements have biological role giving off radiation 6 elements = 98.5% of body weight -oxygen, carbon, hydrogen, nitrogen, calcium, Radioisotopes and phosphorus -unstable isotopes that give off radiation Trace elements in minute amounts -every element has at least one radioisotope Minerals Radioactivity -Inorganic elements extracted from soil by -radioisotopes decay to stable isotopes plants and passed up the food chain to humans releasing radiation Ca, P, Cl, Mg, K, Na, I, Fe, -we are all mildly radioactive -constitute about 4% of body weight Structure (teeth, bones, etc) Enzymes Radiation and Madame Curie Marie Curie Electrolytes -First woman to receive Nobel Prize (1903) -needed for nerve and muscle function are -First woman in the world to receive a Ph.D. mineral salts -first to coined the term ‘radioactivity’ -discovered radioactivity of polonium and Atomic structure radium John Dalton -trained physicians in use of X-rays and -English chemist, developed the atomic theory pioneered radiation therapy as cancer in 1803 treatment -Died of radiation poisoning at 67 Neils Bohr -Danish physicist, proposed a planetary model Ionizing Radiation of atomic structure, similar to planets orbiting the sun -High energy radiation ejects electrons from atoms Nucleus converting atoms to ions -center of atom -deadly in high doses, in low doses, mutagenic -protons: single + charge, mass = 1 and carcinogenic -neutrons: no charge, mass = 1 -Destroys molecules and produces dangerous free radicals and ions in human tissue  -sources include: -chemical particles composed of two or more -UV light, X-rays, nuclear decay atoms united by a chemical bond Compounds α particle (dangerous if inside the body) -molecules composed of two or more different -alpha particle elements -2 protons + 2 neutrons can’t penetrate skin Molecular Formula -sunlight -shows elements and how many atoms each β particle (dangerous if inside the body) are present -free electron - penetrates skin few Structural Formula millimeters -location of each atom y particle (emitted from uranium and plutonium) -structural isomers revealed -penetrating; very dangerous gamma rays Molecules -chemical particles composed of two or more Physical half-life atom united by a chemical bond -time needed for 50% to decay into a stable Compounds state -molecules composed of two or more different -nuclear power plants create radioisotopes elements Molecular formula Biological half-life of radioisotopes -shows elements and how many atoms of -time required for 50% to disappear from the each are present body Structural formula -decay and physiological clearance -location of each atom -structural isomers revealed Unit of radiation exposure in sieverts (Sv) -5 Sv or more is usually fatal Structural Formula of Isomers -background radiation = radon gas and cosmic rays Isomers -source = X-rays and radiation therapy -molecules with identical molecular formulae but different arrangement of their atoms Ions and Ionization Molecular Weight Ionization -the molecular weight of a compound is the -transfer of electron from one atom to another sum of atomic weights of atoms Electrolytes Chemical Bonds -salts that ionize in water and form solutions Chemical Bonds capable of conducting an electric current -forces that hold molecules together, or attract -Electrolyte importance one molecule to another -chemical reactivity Types of chemical bonds -osmotic effects (influence water movement) -Ionic Bonds -electrical effects on nerve and muscle tissue -Covalent Bonds -Electrolyte balance is one of the most important -Hydrogen Bonds considerations in patient care -Van der Waals force -Imbalances have ranging effects from muscle cramps, brittle bones, to coma and cardiac arrest Free Radicals -chemical particles with an odd number of electrons - Produced by -normal metabolic reactions, radiation, chemicals -Causes tissue damage -reactions that destroy molecules -causes cancer, death of heart tissue and aging -Antioxidants -neutralize free radicals -in body, superoxide dismutase (SOD) -in diet (Selenium, vitamin E, vitamin C, carotenoids) Molecules and Chemical Bonds Molecules  -relatively weak bonds -very important to physiology -protein structure -DNA structure Van der Waals Forces Van der Waals Forces -weak, brief attractions between neutral atoms -fluctuations in electron density in electron cloud of a molecules creates polarity for a moment, and can attract adjacent molecules in the region for a very short instant in time -only 1% as strong as a covalent bond -when two surfaces or large molecules meet, the attraction between large numbers of atoms can create a very strong attraction -important in protein folding -important with protein binding with hormones -association of lipid molecules with each other Water and Mixture Mixtures -consists of substances physically blended, but not chemically combined -water 50-75% of body weight -depends on age, sex, fat, content, etc. Water -water’s polar covalent bonds and its V-shaped molecule gives water a set of properties that account for its ability to support life -is the universal solvent Ionic Bonds -solvency -The attraction of a cation to an anion -cohesion -electron donated by one and received by the -adhesion other -chemical reactivity -relatively weak attraction that is easily -thermal stability disrupted in water, as when salt dissolves Solvency -ability to dissolve other chemicals Covalent Bonds -water is called the UNIVERSAL SOLVENT -formed by sharing electrons -Hydrophilic - substances that dissolve in -Types of covalent bonds water -single - sharing of single pair electrons -molecules must be polarized or charged -double - sharing of 2 pairs of electrons -Hydrophobic - substances that do not -nonpolar covalent bond dissolve -shared electrons spend approximately in water equal -molecules are joj-polar or neutral (fat) time -virtually all metabolic reactions depend on the -strongest of all bonds solvency of water -polar covalent bond Adhesion -if shared electrons spend more time -tendency of one substance to cling to another orbiting one nucleus than they do the other, Cohesion they -tendency of like molecules to cling to each other lend their negative charge to the area they -surface film on surface of water is due to spend most time molecules being held high together by a force called -electrons shared unequally surface tension Chemical Reactivity -is the ability to participate in chemical reactions Hydrogen Bonds Hydrogen Bonds -a weak attraction between a slightly positive Thermal Stability of Water hydrogen atom in one molecule and slightly negative -water helps stabilize the internal temperature of oxygen or nitrogen atom in another the body -water molecules are weakly attracted to each Solutions other by hydrogen bonds  --consists of particles of matter called the solute -to prevent too much acidity mixed with a more abundant substance (usually water) called the solvent Work and Energy -Solute can be gas, solid or liquid Energy Colloids -capacity to do work -most common colloids in the body are mixtures of -to do work means to move something protein and water Potential Energy -many can change from liquid to get state within -energy contained in an object because of its and between cells position of internal state -chemical energy - potential energy stored Suspensions and Emulsions in Suspension the bonds of molecules -define by the following physical properties -free energy - potential energy available in -particles exceed 100 nm a -e.g., blood system to do useful work Emulsion Kinetic Energy -suspension of one liquid in another -energy of motion; energy that is actively doing -fat in breast milk work -fluid inside the fluid -heat - kinetic energy of molecular motion -electromagnetic energy - the kinetic Measures of Concentration energy of moving ‘packets’ of radiation Percentages called photons -weight/volume of solute in solution Molarity -known number of molecules per volume Chemical Reaction -(M) is the number of moles of solute/liter of Chemical reaction solution -a process in which a covalent or ionic bond is formed or broken Percentage vs. Molar Concentrations Chemical equation Percentage -symbolizes the course of a chemical reaction -# of molecules unequal Classes of chemical reactions -weight of solute equal -decomposition reactions Molar -synthesis reactions -# of molecules equal -exchange reactions -weight of solute unequal Decomposition Reactions -large molecule breaks down into two or more Electrolyte Concentrations smaller ones Electrolytes -AB – A+B -are important for their chemical, physical and Synthesis Reactions electrical effects on the body -two or more small molecules combine to form a -electrical effects determine nerve, heart, and larger one muscles actions -A+B – AB -Measured in equivalents (Eq) Exchange Reactions -in the body, expressed as milliequivalents -two molecules exchange atoms or group of atoms (mEq/L) -AB+CD – ABCD – AC+BD Acids, Bases and pH Reversible Reactions -an Acid is proton donor (releases H+ ions in -can go either direction under different water) circumstances -a Base is proton acceptor -symbolized with double-headed arrow -pH a measure derived from the molarity of H+ Law of mass action determines direction -a pH of 7.0 is neutral pH -proceeds from the side of equation with greater -a pH of less than 7 is acidic solution quantity of reactants to the side with the lesser -a pH of greater than 7 is basic solution quantity Equilibrium pH -exists in reversible reactions when the ratio of -measurement of molarity of H+ on a logarithmic products to reactants is stable scale -a charge of one number on the pH scale Reversible Rates represents a 10 fold change in H+ concentration -basis for chemical reactions is molecular motions -Our body uses buffers to resist changes in pH and collisions -pH of blood ranges from 7.35 to 7.45 Reaction Rates affected by: Buffers Concentration -forms long chains, branched molecules and -reaction rates increase when the reactants are rings more concentrated -forms covalent bonds with hydrogen, oxygen, Temperature nitrogen, sulfur, and other elements -reaction rates increase when the temperature -carbon backbone carries a variety of functional rises groups Catalysts -substances that temporarily bond to reactants, Monomers and Polymers hold them in favorable position to react with each Macromolecules - very large organic molecules other, and may change the shapes of reactants in ways - very high molecular weights that make them more likely to react -proteins, DNA Enzymes Polymers -most important biological catalysts -molecules made of a repetitive series of identical or similar subunits (monomers) Metabolism Monomers -all chemical reactions of the body -an identical or similar subunits Catabolism -energy releasing (exergonic) decomposition Polymerization reactions -joining monomers to form a polymer Anabolism -dehydration synthesis (condensation) is how -energy storying (endergonic) synthesis reactions living cells form polymers Catabolism and Anabolism are inseparably linked -a hydroxyl (-OH) group is removed from one monomer, and a hydrogen (H+) from another Oxidation-Reduction Reactions -producing water as a by-product Oxidation Hydrolysis -any chemical reaction in which a molecule gives -opposite of dehydration synthesis up electrons and releases energy -a water molecule ionizes into -OH and H+ -molecule oxidized in the process -the covalent bond linking one monomer to -electron acceptor molecule is the oxidizing agent -the other is broken the-OH is added to one Reduction (endergonic) monomer -any chemical reaction in which a molecule gains -the H+ is added to the other electrons and energy -molecule is reduced when it accepts electrons Dehydration Synthesis -molecule that donates electrons is the reducing -Monomers covalently bond together to form a agent polymer with the removal of a water molecule Oxidation-reduction (redox) reactions -A hydroxyl group is removed from one -oxidation of one molecule is always accompanied monomer and a hydrogen from the next by the reduction of another -Electrons are often transferred as hydrogen atoms Hydrolysis -Splitting a polymer (lysis) by the addition of a water molecule (hydro) -a covalent bond is broken -All digestion reactions consists of hydrolysis reactions Organic Molecules: Carbohydrates Organic Chemistry -hydrophilic organic molecule -study of compounds containing carbon -names of carbohydrates often built from: -ability of carbon to form covalent bonds -word root 'sacchar-' 4 categories of carbon compounds -the suffix '-ose' -carbohydrates -both mean 'sugar' or 'sweet' -lipids -monosaccharide or glucose -proteins -nucleotides and nucleic acids Monosaccharides -Simplest carbohydrates Organic Molecules and Carbon -simple sugars -4 valence electrons -3 important monosaccharides -binds with other atoms that can provide it -glucose, galactose and fructose with four more electrons to fill its valence shell -produced by digestion of complex -carbon atoms bind readily with each other carbon carbohydrates backbones - glucose is blood sugar Disaccharides -Sugar molecule composed of 2 monosaccharides -3 important disaccharides -sucrose - table sugar -glucose + fructose -lactose - sugar in milk -glucose + galactose -maltose - grain products -glucose + glucose Oligosaccharides -short chain of 3 Polysaccharides -long chains of glucose -3 polysaccharides of interest in humans Glycogen -energy storage polysaccharide in animals -made by cells of liver, muscles, brain, uterus, and vagina Starch -energy storage polysaccharide in plants -only significant digestible polysaccharide in the human diet Cellulose -structural molecule of plant cell walls 2-72 - fiber in our diet Carbohydrate Functions -quickly mobilized source of energy -all digested carbohydrates converted to Organic Molecules: Lipids glucose -hydrophobic organic molecule -oxidized to make ATP -composed of carbon, hydrogen and oxygen Conjugated carbohydrate -with high ratio of hydrogen to oxygen -covalently bound to lipid or protein -Less oxidized than carbohydrates, and thus has -glycolipids more calories/gram -external surface of cell membrane -Five primary types in humans -glycoproteins -fatty -external surface of cell membrane -acids -mucus of respiratory and digestive tracts -triglycerides -proteoglycans (mucopolysaccharides) -phospholipids -gels that hold cells and tissues together -eicosanoids -forms gelatinous filler in umbilical cord and -steroids eye Lipids -joint lubrication -hydrophobic organic molecules with high ratio of -tough, rubbery texture of cartilage hydrogen to oxygen Fatty Acids Chain of 4 to 24 carbon atoms -carboxyl (acid) group on one end, methyl group on the other and hydrogen bonded along the sides Classified -saturated - carbon atoms saturated with hydrogen -unsaturated - contains C=C bonds without hydrogen -polyunsaturated - contains many C=C bonds -essential fatty acids - obtained from diet, body can not synthesize Triglycerides (Neutral Fats) 3 fatty acids covalently bonded to three carbon alcohol, glycerol molecule -each bond formed by dehydration synthesis  -once joined to glycerol, fatty acids can no longer donate protons neutral fats -broken down by hydrolysis triglycerides at room temperature -when liquid called oils -often polyunsaturated fats from plants -when solid called fat -saturated fats from animals Primary Function -energy storage, insulation and shock absorption (adipose tissue) Phospholipids -similar to neutral fat except that one fatty acid replaced by a phosphate group -structural foundation of cell membrane Amphiphilic -fatty acid "tails" are hydrophobic -phosphate "head" is hydrophilic Trans-fatty acids -hard to breakdown Organic Molecules: Proteins -Greek word meaning "of first importance" -most versatile molecules in the body Eicosanoids Protein -20 carbon compounds derived from a fatty acid -a polymer of amino acids called arachidonic acid Amino acid -hormone-like chemical signals between cells -central carbon with 3 attachments -includes prostaglandins - produced in all tissues -amino group (NH2), carboxyl group (COOH) -role in inflammation, blood clotting, hormone and radical group (R group) action, labor contractions, blood vessel -20 amino acids used to make the proteins are diameter identical except for the radical (R) group -properties of amino acid determined by -R Steroids and Cholesterol group Steroid -a lipid with 17 of its carbon atoms in four rings Naming of Peptides Cholesterol Peptide -the 'parent' steroid from which the other steroids -any molecule composed of two or more amino are synthesized acids joined by peptide bonds -cortisol, progesterone, estrogens, Peptide bond testosterone -joins the amino group of one amino acid to the and bile acids carboxyl group of the next Cholesterol -formed by dehydration synthesis -synthesized only by animals Peptides named for the number of amino acids -especially liver cells -dipeptides have 2 -15% from diet, 85% internally synthesized -tripeptides have 3 -important component of cell membranes -oligopeptides have fewer than 10 to 15 -required for proper nervous system function -polypeptides have more than 15 -proteins have more than 50 “Good" and "Bad" Cholesterol -one kind of cholesterol Protein Conformation and Denaturation -does far more good than harm Conformation -'good' and 'bad' cholesterol actually refers to -unique three dimensional shape of protein crucial droplets of lipoprotein in the blood to function -complexes of cholesterol, fat, phospholipid, -ability to reversibly change their conformation and protein -enzyme function HDL - high-density lipoprotein -muscle contraction -"good" cholesterol -opening and closing of cell membrane pores -lower ratio of lipid to protein -may help to prevent cardiovascular disease Denaturation LDL - low-density lipoprotein -extreme conformational change that destroys -"bad" cholesterol function -high ratio of lipid to protein -extreme heat or pH -contributes to cardiovascular disease Protein Structure and Shape -Naming Convention Primary structure -named for substrate with -ase as the suffix -protein's sequence amino acid which is encoded -amylase enzyme digests starch (amylose) in the genes Lowers activation energy Secondary structure -energy needed to get reaction started -coiled or folded shape held together by hydrogen -enzymes facilitate molecular interaction bonds Tertiary structure Enzyme Structure and Action -further bending and folding of proteins into -Substrate approaches active site on enzyme globular and fibrous shapes molecule -globular proteins -compact tertiary structure -Substrate binds to active site forming well suited for proteins embedded in cell enzyme-substrate complex and proteins that must move about freely in -highly specific fit -'lock and key' body fluid -enzyme-substrate specificity -fibrous proteins - slender filaments better -Enzyme breaks covalent bonds between suited for roles as in muscle contraction and monomers in substrate strengthening the skin -adding H+ and OH- from water - Hydrolysis Quaternary structure -Reaction products released - glucose and -associations of two or more separate polypeptide fructose chains -Enzyme remains unchanged and is ready to repeat -functional conformation - three dimensional the process shape Cofactors and Coenzymes Protein Functions Cofactors Structure -about 2/3rds of human enzymes require a -keratin tough structural protein nonprotein cofactor -gives strength to hair, nails, and skin surface -inorganic partners (iron, copper, zinc, magnesium -collagen and calcium ions) -durable protein contained in deeper layers of -some bind to enzyme and induces a change in its skin, bones, cartilage, and teeth shape, which activates the active site Communication -essential to function -some hormones and other cell-to-cell signals Coenzymes -receptors to which signal molecules bind -organic cofactors derived from water-soluble -ligand any hormone or molecule that vitamins (niacin, riboflavin) reversibly -they accept electrons from an enzyme in one binds to a protein metabolic pathway and transfer them to an enzyme in Membrane Transport another -channels in cell membranes that governs what passes through Organic Molecules: Nucleotides - carrier proteins - transports solute particles to 3 components of nucleotides other side of membrane -nitrogenous base (single or double carbon- -turn nerve and muscle activity on and off nitrogen ring) Catalysis -sugar (monosaccharide) -enzymes -one or more phosphate groups Recognition and Protection ATP -immune recognition -best know nucleotide -antibodies -adenine (nitrogenous base) -clotting proteins -ribose (sugar) Movement -phosphate groups (3) -motor proteins - molecules with the ability to change shape repeatedly Adenosine Triphosphate (ATP) Cell adhesion -body's most important energy-transfer molecule -proteins bind cells together -briefly stores energy gained from exergonic -immune cells to bind to cancer cells reactions -keeps tissues from falling apart -releases it within seconds for physiological work -holds energy in covalent bonds -2nd and 3rd phosphate groups have high Enzymes energy Enzymes Bonds -proteins that function as biological catalysts -most energy transfers to and from ATP -permit reactions to occur rapidly at normal involve adding or removing the 3rd phosphate body temperature Adenosine triphosphatases (ATPases) -Substrate - substance an enzyme acts upon -hydrolyze the 3rd high energy phosphate bond  -separates into ADP + P + energy Phosphorylation -addition of free phosphate group to another molecule 2-106 -carried out by enzymes called kinases (phosphokinases) Other Nucleotides Guanosine triphosphate (GTP) -another nucleotide involved in energy transfer -donates phosphate group to other molecules Cyclic adenosine monophosphate (cAMP) -nucleotide formed by removal of both second and third phosphate groups from ATP -formation triggered by hormone binding to cell surface -CAMP becomes "second messenger" within cell -activates metabolic effects inside cell Nucleic Acids -polymers of nucleotides DNA (deoxyribonucleic acid) -100 million to 1 billion nucleotides long -constitutes genes -instructions for synthesizing all of the body's proteins - transfers hereditary information from cell to cell and generation to generation RNA (ribonucleic acid) – 3 types -messenger RNA, ribosomal RNA, transfer RNA -70 to 10,000 nucleotides long -carries out genetic instruction for synthesizing proteins -assembles amino acids in the right order to produce proteins