Chapter 1 Introduction 09 16 2013 Anatomy and Physiology Anatomy is the study of the structure of the body Physiology is the study of how the body functions and works together Hippocrates believed diseases could be attributed to natural causes not Aristotle believed structures are formed from smaller simpler gods and demons components Galen used animal cadavers instead of human cadavers because it was taboo and illegal to look at human cadavers those who looked at human cadavers were grave diggers pig cadavers are closest to human cadavers Hierarchy of Complexity we are considered organisms organisms are composed of organ systems Organ systems are composed of organs Organs are composed of tissues Tissues are composed of cells Cells are composed of organelles organelles are structures that are part of cells but could not function on their own organelles are composed of molecules such as proteins and fats molecules are composed of atoms Components of an Organism Organ system is a group of organs with a unique collective function Variations in Anatomy Not every individual is identical anatomically Anatomical atlases provide the most common structures Organs are in reverse positions sometimes o Does not have much of an influence We have some muscles that are no longer functional Characteristics of Life A high level of organization Compartmentalization of functions Metabolism sum of anabolism and catabolism o anabolism formation of larger molecules from smaller building blocks protein synthesis o catabolism breakdown of larger molecules into smaller building blocks protein digestion Responsiveness to stimuli Homeostasis internal stability Development differentiation and growth Reproduction Evolution able to adapt to our circumstances Homeostasis homeostasis Maintaining the body at stable conditions correct for slight changes Set point optimal value typically fits within range of optimal values the body is able to maintain specific conditions o examples metabolisms blood pressure temperature blood acidity heart rate etc Negative feedback the body senses a value has changed from its set point and makes changes to return it to the set point Think of it like a thermostat regulating a house with a c and heat Components of a negative feedback loop o Receptor detects a change o Control center integrates the information and decides what to do to return the body to its set point a lot of times the control center will be our brain o effector carries out the changes as determined by the brain Your body is set to a temperature of approximately 98 6 F What happens when your body temperature is too high o your blood vessels dilate and you sweat o hydrate expand your body parts fan yourself what happens when your body temperature is too low o You shiver you cramp blood vessels constrict o rub your arms move around put on more layers drink something hot Positive feedback the change is not returned to the set point but rather is amplified until signaled to stop Takes body away from homeostasis o example is childbirth baby s head puts pressure on the cervix signal is sent via nerves to the brain brain releases oxytocin uterus contracts pushing head towards cervix baby s head puts pressure on the cervix etc what signals positive feedback to stop o baby being born Orientation and Directional Terms Anatomical position person stands with arms at their sides palms facing forward Provides a reference for anatomical and directional terms Anatomical planes imaginary lines cutting through the body o Sagittal plane separates the body into left and right o Frontal coronal plane separates the body into front and back o Transverse plane separates the body into top and bottom Chapter 2 Chemistry 09 16 2013 Elements Atoms o Element simplest form of matter to have unique chemical properties o 98 5 of body weight is from oxygen carbon hydrogen nitrogen calcium phosphorus Minerals o Some elements are classified as minerals o Minerals inorganic elements used by humans o Main contributors are chloride madnesium potassium sodium sulfur o Bones and teeth o Proteins o Nucleic acids ATP cell membranes o Thyroid hormones o Hemoglobin Ions o Ions have unequal numbers of protons and electrons through a transfer of electrons called ionization o May be a single atom or an entire protein o Anion ion with a net negative charge as a result of gaining electrons o Examples Cl o Cation ion with a net positive as a result of losing electrons o Examples K Na H Ca2 Ions electrolytes free radicals o Electrolytes ionize in water and can conduct electricity o Include acids bases salts o In our bodies electrolytes are important for proper functioning of muscles heart nervous system bones o Free Radicals have an od number of electrons making them unstable o Often formed through normal metabolism and can harm molecules o Superoxide is a common free radical O2 o We make natural antioxidants Molecules and Bonds o Two or more atoms can be joined together through chemical bonds to o Molecules may be formed from two identical atoms or two or more form molecules different atoms Oxygen O2 Glucose C6H12O6 bonds hydrogen bonds bond o Three types of bonds from strongest to weakest covalent bonds ionic Covalent bonds electrons are shared by the atoms involved in the o May form single bonds represented by one line o Double bonds represented by two lines o Triple bonds represent by three lines o What determines how many bonds The number of valence electrons o Bonds may be polar or nonpolar neutral o If the sharing of electrons is even the bond is nonpolar and there is no net pull in one direction Ionic bonds are formed between an anion and cation o Na and Cl o May be formed between more than two ions o Ca2 and two ions of Cl o Ionic bonds are easy to break o Commonly dissociate in anything more attractive such as water o Think about what happens when you put table salt in to a glass of water it dissolves o Sodium and chloride are more attracted to the water than they are to each other Hydrogen Bonds are very weak involving a hydrogen atom and a slightly negative atom o Very common in DNA and proteins o Help to stabilize DNA and proteins by having MANY hydrogen bonds about two or three Water o Water makes up about 50 75 of our body weight depending on o Age less with age o Sex females have more o Fat content more fat content more water o Keep in mind that water is polar with a net negative region and a net positive region allowing it to form bonds with many