Anatomy & Physiology 
Health professionals speak a foreign language called medical terminology
This chapter lays the foundation for learning this new language
Future chapters build upon the foundation that begins here, so at journey’s end you will not only understand anatomy, physiology, and disease, but be fluent in the language
Anatomy 
Study of internal and external structures of the human body
Human body is complex and amazing; to truly understand it you must know how it is put together
Whenever we look at our own body or study large body structures like our heart, we are observing gross anatomy
Anatomy is a Greek word meaning “to cut apart”
Specialties within field of anatomy include microscopic anatomy (too small to be seen with the naked eye) and macroscopic (gross) anatomy
Physiology 
Focuses on function and vital processes of various structures making up the human body
It is the study of how the body and its parts work or function
Closely related to anatomy because it is the study of how anatomical structures actually function
Deals with all vital processes of life; is more complex, with more sub-specialties
Subspecialties
Human physiology
Animal physiology
Cellular physiology
Neurophysiology
Metabolism 
Anatomy focuses on structures and how something is put together
Physiology is the study of how these different structures work together to make the body function as a whole
Anatomy would be the study of the structure of RBCs, and the physiology would be the study of how the RBCs carry vital oxygen throughout our body
Design of the structure is often related to its function
Why study anatomy and physiology?
Human anatomy and physiology (A&P) forms the foundation for all medical practice
Medical treatment attempts to bring the body’s structure and function back to normal A&P
What is disease?
Disease (meaning not at ease) is a condition in which the body fails to function normally 
The body works to make things function smoothly and maintain balance known as homeostasis
Pathology is the study of disease characteristics, causes, and effects
Pathophysiology is the study of abnormal body function
Terms related to disease
Etiology: cause of the disease, is important to determine
Nosocomial- acquired in the hospital
Epidemiology: study of the transmission, frequency of occurrence, distribution, and control of a disease 
An epidemiologist determined that there are nearly 62 million cases of the common cold each year
Getting or giving a medical history helps determine the etiology
Types of diseases
A communicable and contagious disease may sound like they are the same thing but there is a fine difference:
Communicable diseases: those that have potential to be spread from person to person
Contagious diseases: readily transmitted from one person to another Like the common cold
Center for Disease Control (CDC) tracks disease worldwide 
Endemic: diseases that occur in specific populations or regions
Epidemic: when diseases occur in large numbers over specific region
Pandemic: when diseases spread country or worldwide
Refers to all chemical operations going on within the body
Requires various nutrients
Produces waste products
Includes all life-sustaining reactions within the body
Two types: anabolism and catabolism
Fever is common disease process that will speed up metabolism
Anabolism 
First type of metabolism
Building phase of metabolism
Process of simple compounds being built up and then used to manufacture materials for growth, reproduction, and repair
Example would be the assembly of simple amino acids to form complex protein
Catabolism 
2nd type of Metabolism:
Breaking down phase of metabolism
Process by which complex substances are broken down into simpler substances
Example: breakdown of food into simpler chemical building blocks for energy
Abnormal and extreme example: starvation victim whose body will “feed upon itself” by actually consuming own body’s tissues
Homeostasis 
For the body to remain alive, it needs to constantly monitor the internal and external environment and make appropriate adjustments.
In order for cells to remain alive and thrive they need an appropriate environment to live in as well (temperature, HR, balanced oxygen levels)
Physiological process that monitors and maintains a stable internal environment or equilibrium
Survival depends on ability to maintain homeostasis
Homeostatic regulation refers to adjustments made in human organism to maintain a stable internal environment
For example, a thermostat is a homeostatic control in a home
The thermostat in your house works by a..
Continuous feedback loop to determine what required action is needed
If feedback opposes the stimulus, it is a negative feedback loop
Hypothalamus in the brain uses a negative feedback loop to control body temperature and maintain homeostasis
Positive feedback loop
Increases magnitude of change versus resisting change
Process known as a vicious cycle
Does not maintain homeostasis but sometimes necessary to complete a specific process
It is not a way to regulate the body because it increases change away from the ideal set point
Often harmful if cycle cannot be broken
Example: recurrent contraction of uterus during childbirth
Baby is ready to be born Oxytocin is released from the posterior pituitary
Oxytocin increases the intensity of the uterine contractions
As uterus contracts pressure inside the uterus increases the signal to the hypothalamus and it tells the posterior pituitary to release more Oxytocin
Uterus contracts even harder
This process keeps occurring until the baby is born and the pressure in the uterus is decreased.
Signs - objective, measurable indicators of illness
Examples: fever, change in color
Vital signs: signs vital to life and can have different normal values according to age and sex 
Pulse
Blood Pressure
Temperature
Respiratory Rate
In some health care settings weight is being accepted as a vital sign
Symptoms: subjective indicators of illness that are perceived only by the patient 
Examples: pain, dizziness, itchiness
Each person tolerates these differently so it is hard to measure
Still important because a disease shows a set groups of signs and symptoms that occurs the same time (Syndrome)
Syndrome: a specific grouping of signs and symptoms related to a specific disease
Example: Down Syndrome signs and symptoms include sloping forehead, low set ears, short broad hands, mild-to-moderate mental retardation, and often, cardiac Valvular disease
Discovering as many s/sx as possible helps to diagnose a disease.
Diagnosis: identification of disease determined by studying patient’s signs, symptoms, history, and results of diagnostic tests 
Begins by obtaining Chief Complaint (CC) or reason the individual is seeking medical help
Going to the doctor with a CC of a cough since June
Continues as more details are obtained about the problem
The Dr. asks more questions with his assessment….short of breath, what makes it worse, better?
If cause cannot be determined it is known as an idiopathic disease
Prognosis: prediction about outcome of a disease
Remember symptoms from a disease may have just started or have been there for a long time
Acute conditions: rapid onset of signs and symptoms
Chronic conditions: gradual onset of symptoms over a long period of time
Remission: period of time when signs and symptoms of chronic disease disappear
Cohn's Disease or Sickle Cell
Relapse: recurrence of a disease
Exacerbation: “flare-up” of signs and symptoms
MS (multiple sclerosis)
Terminal disease: one with a prognosis of death
Body Defense Systems
Microorganisms that enter the body are harmless but..sometimes they can produce a disease and that is said to be a
Disease can result from pathogenic (disease producing) microorganisms invading body through openings referred to as portals of entry
Body Barriers: first line of defense
Example: skin
Slightly acidic so it provides an environment that many harmful organisms don’t like.
Provides mechanical barrier (if unbroken )
Immune response: kicks in if pathogens get past barriers (this is the second line of defense for the body…or the second barrier that comes into action when a germ gets through the barrier) 
Microscopic body cells activate
Some attack and “eat” pathogens
Some release powerful chemicals that disintegrate pathogens
If body has been attacked by that pathogen before, substances can be produced that specifically target that pathogen
Specific immune response
Allergic or hypersensitivity reaction is when you have an allergic reaction causing the immune system to go too far; this causes tissue damage and impairs normal function
Inflammatory response - occurs whenever body tissues are injured 
Possible triggers: physical injury, intense heat, chemical irritation, reaction to invading germs (infection)
Signs and symptoms: redness, increased temperature at affected site, swelling (edema), pain
Is normally a protective function: Isolates injured area, Increases blood flow to restore normal function
Routes of Transmission 
Germs/pathogens gain entrance to your body by four main routes:
Vector 
Contact transmission 
Common vehicle 
Airborne 
Vectors: when disease is spread by insect, or other non-human animal
Biological vector: infected insect spreads infection to person (example: malaria)
Mechanical vector: organism present on surface of insect is spread to person (example: a fly that lands on cow feces, and then on a person’s food)
Direct contact: when a person becomes sick due to direct contact with a contagious body fluid
Pt has bm in bed and the feces comes into contact with an open wound on the patients buttock
Health care provider cleans a wound and does not glove up
Indirect contact: when a person becomes sick due to contact with a contaminated object (example: catching the flu by picking up germs from a doorknob)
Common vehicles: when consumable goods (such as food, or blood, or medications) become contaminated; results in several people simultaneously developing same infection
This is a set up for a major epidemic
Airborne spread: when droplets containing a pathogen spread through the air
Example: TB, or pathogens growing in an air conditioner (Legionnaires Disease)
Preventing the spread of infection 
Requires breaking the chain of infection (interrupting spread of disease from outside source into the body)
Washing your hands is one of the most powerful ways of controlling the spread of disease
There was a time when there was no attention focused on the healthcare provider and the pt- it was always the disease itself.
We don’t always recognize infectious agents and so it can be easy to spread without our awareness
Because we don’t always know if and when we will spread an agent (pathogen, infectious disease) Standard Precautions were developed
Universal Precautions/Standard Precautions: set of standard actions/procedures designed to prevent transmission of disease between patient and health care provider
Based on assumption that every person could have some kind of communicable disease
Provide the basic protection for both HCP and pt
Includes use of gloves, gowns, goggles, masks, and other protective equipment ( PPE) in appropriate situations