HTHS 1110 / Biomedical Core Module 1

HTHS 1110 / Biomedical Core Module 1 Body Plan & Organization Homeostasis Disease: A Disruption in Homeostasis Measurement Systems and Calculations Used for the Human Body

Body Plan & Organization

Anatomy vs. Physiology Anatomy (study of structure) Word is from Greek: ανα-, on/up/backwards/through/towards -τομη, cutting Anatomy = cutting backwards, putting things together from slices Physiology (study of function) υυσις-, nature -λογος, study Includes homeostasis, the systems that keep the body in balance see footnote 1 Objective 1

Structure and Function Structure and function are complementary to each other. Structure determines functional possibilities. Structure designs the specific function. Function influences the size, shape, action, and reaction of the structure. Objective 2

Structure and Function Example This structure is the liver, which has the function of filtering blood and producing bile. Can you see how the function is determined by the structure, and vice versa? Objective 2

Subdivisions of Anatomy Embryology The first 8 weeks of development Developmental Biology All stages of development Cell Biology Cell structure and function Histology Microscopic structure of tissues Surface Anatomy Surface markings of the body Gross Anatomy Structures viewed without a microscope Systemic Anatomy Structure of specific systems Regional Anatomy Specific regions of the body Radiographic Anatomy Body structures visualized with X-ray, CT, or MRI Pathological Anatomy Structural changes with disease Objective 3

Subdivisions of Anatomy Objective 3

Subdivisions of Physiology Neurophysiology Functional properties of nerve cells Endocrinology Hormones and how they control body functions Cardiovascular physiology Function of the heart and blood vessels Immunology How the body defends itself against diseasecausing agents Respiratory physiology Functions of the air passageways and lungs Renal physiology Functions of the kidneys Exercise physiology Changes in cell and organ functions as a result of muscular activity Pathophysiology Functional changes associated with disease and aging Objective 4

Subdivisions of Physiology Objective 4

Levels of Organization Chemical Atomic Molecular Cellular Tissue Organ System Organism smallest Modules 1-7 largest Objective 5

Raven, Environment, 7e Objective 5

Movie showing levels of organization http://www.wehi.edu.au/uploads/wehi-tv/body_code.mov (8:36)

Integumentary (Skin) Module 8 Objective 6 Skeletal Module 9

Muscular Module 10 Objective 6 Nervous Modules 11 13

Endocrine Module 14 Objective 6 Cardiovascular Modules 15 16

Lymphatic & Immune Module 15 Objective 6 Respiratory Module 17

Digestive Module 18 Objective 6 Urinary Module 19

Reproductive (these organs, the primary sexual characteristics, define the two human genders) Female Male Module 20 Objective 6

Systems of the Body The systems of the body may appear to be separate and distinct in their functions, but the maintenance of normal body function requires the integration of many systems. Body temperature: integumentary, muscular, cardiovascular, and nervous Body fluid composition: urinary, digestive, respiratory, and cardiovascular Objective 6

Levels of Organization Chemical Atomic Molecular Cellular Tissue Organ System Organism smallest Modules 1-7 largest Objective 6

Human Anatomical Position In the anatomical position the subject stands erect facing the observer with the head level, the eyes facing forward, feet flat on the floor, feet directed forward, and the arms at their sides with the palms facing forward. All anatomical descriptions are in reference to this position. Objective 7

Ireland, Visualizing Human Biology, 2e Objective 8

Superior Inferior Medial Lateral Proximal Distal Anterior Posterior this arm is ipsilateral to this leg Ventral Dorsal this leg is contralateral to this arm Ipsilateral Contralateral Objective 9

parietal visceral superficial superficial deep superficial superficial Objective 9

Cardinal Body Sagittal Planes Midsagittal Divides the body into two equal, mirror-image halves Parasagittal Parallel to sagittal, but not through the midline Transverse (Horizontal) Frontal (Coronal) Objective 10

*note the relationship between the plane of section and the shape of the section that s anatomy! (See Objective 14.) Sagittal (Midsagittal) Frontal (Coronal) Transverse (Horizontal) Objective 10

Cardinal Planes in Imaging Objective 10

Body Cavities Objective 11

Major Body Organs Objective 12

Major Body Organs Brain + Cranial Nerves Spinal Cord + Spinal Nerves Objective 12

Anatomy and Physiology for the Manual Therapies, 1e Alters, Biology: Understanding Life, 1/e Objective 12

Objective 12

Heart Superior vena cava Inferior vena cava Aorta Objective 12

Major Body Organs & Structures Diaphragm (divides thorax from abdomen) Objective 12

Trachea Esophagus Stomach Liver Small Intestine Large Intestine Objective 12

Objective 12 Anatomy and Physiology from Science to Life, 2/e

Objective 12 Introduction to the Human Body, 8e

Objective 12

Objective 12 Anatomy and Physiology from Science to Life, 2/e

Objective 12

Quadrants and Regions of the Abdominopelvic Cavity Identification of quadrants and regions in the abdominopelvic cavity helps clinicians describe the location of the many abdominal and pelvic organs. There are 4 abdominopelvic quadrants and 9 regions. The dividing lines between these are centered on the umbilicus ( belly button ) Objective 13

Objective 13

RUQ liver LUQ spleen left kidney RLQ cecum (where small intestine meets large) appendix LLQ left ovary (if this were a woman) Objective 13

Cross-Sectional Anatomy: Thorax Identify: Pleural cavity Pericardial cavity Heart Right lung Aorta Thymus Left lung Esophagus Tortora & Derrickson Figure 1.10 Objective 14

Cross-Sectional Anatomy: Head Imaging modalities are methods used to see anatomy X-rays are a modality These images are from the Visible Human Project From top to bottom: photograph of frozen, sawed head computed tomography (CT) scan of the same level/plane magnetic resonance imaging (MRI) scan of the same level/plane Note brain in each section: how does it appear different depending on modality? http://vhp.med.umich.edu/ Objective 14

Cross-Sectional Anatomy: Thorax This section through the thorax is about the same level/plane as Tortora & Derrickson fig 1.10 Find: lungs (left and right), thymus, esophagus, aorta, heart Why is the lung on the right side of this drawing labeled left lung? http://www.up.ac.za/academic/medicine/ http://vhp.med.umich.edu/ anatomy/current/x/069_16toxa.html Section 1298 Wightman AJA Diagnostic Imaging. In: Crofton & Douglas Respiratory Diseases 5e, 2008 http://vhp.med.umich.edu, Section 1298 Objective 14

http://vhp.med.umich.edu/browsers/images/female/color/transverse/high/1298.jpg http://vhp.med.umich.edu/browsers/images/female/color/sagittal/high/1111.jpg http://vhp.med.umich.edu/browsers/images/female/color/coronal/high/700.jpg Objective 14

Cross-Sectional Anatomy: Abdomen This section is through the lower arms (note two bones) and kidneys Abdominal organs at this level are the liver, spleen, small intestines and kidneys liver sm intestine spleen kidney http://vhp.med.umich.edu/ Section 1798 Objective 14

Identify Major Bones Skull Vertebral Column Sternum Ribs Objective 15

Identify Major Bones Clavicle Scapula Humerus Radius Ulna Carpals Metacarpals Phalanges Objective 15

Identify Major Bones Pelvis Femur Patella Tibia Fibula Ireland, Visualizing Human Biology, 2e Pelvis Tarsals Metatarsals Phalanges Objective 15

Homeostasis Disease: A Disruption in Homeostasis

Homeostasis: A Balancing Act Homeostasis The condition of equilibrium (balance) in the body s internal environment due to the constant interaction of the body s many regulatory processes Objective 16

Homeostasis The condition of equilibrium (balance) in the body s internal environment due to the constant interaction of the body s many regulatory processes Objective 16

Homeostasis Component Receptor Control Center Effectors Function Monitors controlled condition Receives input and provides output Bring about change in controlled condition Objective 17

Negative Feedback Loop Example: Blood Pressure Objective 18

Positive Feedback Loop Example: Childbirth Objective 19

Homeostasis Positive Feedback Characteristics Negative Feedback Characteristics Strengthen or reinforce a change. Action continues until it is interrupted. Reinforces conditions that do not happen very often. Reverses a change in a controlled condition. Action stops automatically when setpoint is reached. Regulate conditions that remain fairly stable over long periods. Objective 20

Homeostasis Positive Feedback Examples Negative Feedback Examples Blood clotting Body temperature Childbirth Blood glucose Severe blood loss Many, many others Objective 20

Disease: A Disruption of Homeostasis

Signs Generalized Signs & Symptoms of Disease Determined by observation of patient i.e., what we see Examples of signs swelling, redness, rashes, pus, fever, vomiting Symptoms Determined by asking the patient i.e., what the patient tells us Examples of symptoms nausea, pain, shortness of breath, headache, generalized malaise Laboratory tests are used to determine presence of infection Objective 21

Syndrome A syndrome is a set of signs and/or symptoms that often occur together Usually, we don t understand the relationship between these For example, in metabolic syndrome, four signs occur together Hypertension (high blood pressure) Dyslipidemia (abnormal fats in blood) Obesity (overweight) Type II diabetes (increased sugar in blood) Objective 21

Abnormal Homeostasis in Autoimmune Disease Objective 22

Diseases from Internal and External Sources Disruptions in homeostasis can be caused by genetic or environmental factors For example, autoimmune diseases are disruptions in the homeostatic loops involved in defense against invaders Disruptions in homeostasis can also be caused by outside agents (infectious disease) More on this in Module 6 Objective 22

Modes of Disease Transmission Contact Transmission Direct (touching, kissing, intercourse) Indirect (fomites: shared objects) Droplet (distance < 1 meter) Common Vehicle Transmission Contaminated food, water, blood Airborne Transmission Pathogens stay alive in droplets or dust traveling > 1 meter The Velveteen Rabbit was a fomite Objective 23

Modes of Disease Transmission Typhoid Mary was a carrier Vector Transmission Organism that transmits disease Tick that transmits Lyme Disease Mosquito that transmits malaria Flies transmit various diseases If the vector is a person who does not appear to be ill, they are called a carrier Objective 23

Infections in Scientist working with the H1N1 influenza virus (note Biosafety Level 3 precautions) PHIL #7988 Populations Sporadic infection Individuals are infected here and there through the population Endemic infection Occur regularly in low to moderate levels in a population within a given geographic area Epidemic infection Disease has a higher-thannormal incidence in a given population Pandemic infection Worldwide epidemic e.g. HIV Objective 23

Nosocomial Infections Nosocomial means hospital acquired Most severe in patients who have problems with their immune system function (immunocompromised) Exogenous Transmitted from external environment Endogenous Infections arise from organisms already present in or on the patient For example, diseases kept in check by immune system begin to cause problems Organisms may be introduced during invasive procedures Objective 23

Universal Precautions Guidelines from CDC to help reduce transmission of infections Hand-washing Protective barriers Strict protocols for the disposal of contaminated needles, scalpels, and other equipment Objective 23

Measurement Systems and Calculations Used for the Human Body

The English System (The US Customary System) Objective 24

Système Internationale d unités (SI) The Metric System Objective 24

Getting Rid of all the Zeroes No one has enough time to write all of the zeroes if we frequently use very small or very large measurements. To alleviate this problem, we have exponents. An exponent is a little number that is raised ½ a space above (superscript) a big number. 10 3, 2 2, 5 3, etc. An exponent tells you how many times you multiply the big number by itself. (2 3 = 2 x 2 x 2) Objective 25

Exponents in the Metric System Working with exponents in the metric system is very easy because it only deals with units of 10. The decimal system is also based on units of 10, so converting from one unit to another requires only the movement of the decimal. If the number is getting bigger (positive exponent), the decimal moves to the right. If the number is getting smaller (negative exponent), the decimal moves to the left. 1x10 3 = 1000.0 and 1x10-3 = 0.001 Objective 25

Metric System Prefixes Objective 25

Converting US Customary to Metric Objective 26

Converting Metric to US Customary Objective 26

Significant Figures We can t create information where none existed before For example, what s one-seventh of a foot? A foot is 12 inches, divide by 7.00 12 inches / 7.00 = 1.714285714285714 inches Rulers aren t that accurate! One-seventh of a foot is 1.7 inches 12 has two significant figures and 1.7 has two significant figures as well Objective 27

What if we don t have a direct conversion factor? A problem-solving technique that converts from one unit to another by using conversion factors is called Dimensional Analysis A (given unit) x B (requested unit) = D (requested unit) C (given unit) Objective 28

Dimensional Analysis or The Factor-Label Method http://bit.ly/dimensionalanalysis http://bit.ly/factorlabel Objective 28

Make the Units Work The philosophy behind Dimensional Analysis (also called the Factor-Label Method ) is that as long as we make the units work out, we can get to the right answer Objective 28

Dimensional Analysis Toolbox What do we need for Dimensional Analysis? 1. Given amount, with units 2. Desired units (we are calculating the amount) 3. Conversion factors Objective 28

Make the Units Work Realize that conversion factors can be turned into fractions that are equal to 1 It s always legal to multiply by 1 it doesn t change anything except the units. Objective 28

Multiplying by 1 to Change Units For example, we know that 1 inch = 2.54 cm So if we divide both sides of the equation by 2.54 cm, we get ( 1 inch ) =( 2.54 cm ) 2.54 cm 2.54 cm ( 1 inch ) = 2.54 cm 1 Objective 28

Putting Conversion Factors to Work 5 cm X ( 1 inch ) 2.54 cm = 5 cm X ( 1 inch ) 2.54 cm = ( 5 2.54 ) inches 5 cm = 1.97 inches Objective 28

Significant Figures We can t create digits where there are none! The original question had one digit; the answer needs to be one digit as well. 5 cm X ( 1 inch ) 2.54 cm = 5 cm X ( 1 inch ) 2.54 cm = ( 5 2.54 ) inches 5 cm = 1.97 inches 5 cm = 2 inches Objective 28