Chapter 1:
Organization of the
Human Body
Do you know who I am?
Leonardo da Vinci’s
The Vitruvian Man
What is Anatomy?
-The science of the structures of the body and their relationships to
each other
-Anatomy includes the study of:
-Body locations
-Cephalic = head
-Pedal = foot
-Directional terms
-Superior = toward the head
-Inferior = away from the head
-Dissection of the body
-Sagittal plane – divides body into left and right sides
Anatomical Position
• Standardized position from which to
describe directional terms
–
–
–
–
–
–
standing upright
facing the observer, head level
eyes facing forward
feet flat on the floor
arms at the sides
palms turned forward
• Prone position = lying face down
• Supine position = lying face up
Tortora & Grabowski 9e  2000 JWS
1-3
Regions of the Body
Page 11
Anatomical Terms
Vertebral
Cephalic
Orbital
Otic
Cervical
Palmer
Manual
Nasal
Sacral
Digital
Oral
Dorsal
Femoral
Mental
Mammary
Patellar
Pedal
Thoracic
Pelvic
Plantar
Carpal
Abdominal
Gluteal
Page 13
Directional Terms
Superior
- Toward the head
Inferior
- Away from the head
Anterior
- Toward the front
Posterior
- Toward the back
Medial
- Toward the middle
Lateral
- Away from the middle
Proximal
- Nearer to the attachment point
Distal
- Farther from the attachment point
Superficial - Toward or on the surface
Deep
- Away from the surface
Page 14
Planes of the Human Body
-Sagittal Plane – a vertical plane that divides the body into right and
left sides
-Midsgittal – equally divided into right and left sides
-Parasagittal – unequally divided into right and left sides
- Frontal Plane (coronal plane) – a plane that divides the body into
anterior and posterior portions
-Transverse Plane – a plane that divides the body into superior and
inferior portions
-Oblique Plane – a plane at an angle between the sagittal plane and
the transverse plane
Anatomy and Physiology
Body Cavities
Page 15
Subdisciplines of Anatomy
Embryology The study of structures that immerge from the time of
the fertilized egg through the eighth week in utero
Developmental The study of structures that emerge from the time of
Anatomy
the fertilized egg to the adult form
Cytology
The study of the chemical and microscopic structure
of cells
Histology
The study of microscopic structures of tissues
Gross
Anatomy
The study of structures that can be examined without
using a microscope
What is Physiology?
- The science of body functions, or how the body parts work
-The stomach digests proteins
-The heart muscle contracts
Subdisciplines of Physiology
Cell Physiology The study of the function of cells
Neurophysiology The study of the functional properties of nerve
cells
Endocrinology
The study of hormones and how they control body
functions
Immunology
The study of how the body defends itself against
disease-causing antigens
Exercise
Physiology
The study of changes in cell and organ function as a
result of muscular activity
Pathophysiology The study of functional changes associated with
disease and aging
Levels of Organization
Chemical
Basic structural and
functional unit of life
Cellular
Tissue
Multiple tissues
working together to
perform a specific
function
Atoms – C,H,O,N,P,S
Molecules – C6H12O6,
CO2, H2O, NaCl
Group of similar cells
working together to
perform a function
Organ
System
Related organs with a
common function
Page 3
4 Basic Animal Tissue Types
1. Connective
– Ex: blood
2. Epithelial
– Coverings; ex: skin, membranes, linings
3. Nervous
– CNS and PNS
4. Muscle
– Locomotion & movement within organs
Body Systems
Nervous
There are 11 body systems:
Integumentary
Immune
Endocrine
Skeletal
Respiratory
Lymphatic
Digestive
Muscular
Cardiovascular
Reproductive
Urinary
Integumentary System
•Anatomy – skin, hair, nails, sweat glands, and oil glands
•Physiology – regulates body temperature, protects the body,
eliminates wastes, receives sensations, produces vitamin D
Skeletal System
•Anatomy – all the bones of the body, and associated cartilage and
joints
•Physiology – supports and protects the body, aid in movement,
produces blood cells, stores minerals
Muscular System
•Anatomy – skeletal muscles
•Physiology – participates in movement, maintains posture, produces
heat
Nervous System
•Anatomy – brain, spinal cord, nerves, and sense organs
•Physiology – regulates body activities, detects changes in the
environment, brings about muscular contractions and glandular
secretions
Endocrine System
•Anatomy – all the glands and tissues that produce hormones
•Physiology – Regulate body activities through hormones that are
specific to target organs
Cardiovascular System
•Anatomy – blood, heart, and blood vessels
•Physiology – transports O2, CO2, nutrients, wastes, hormones, and
other dissolved substances throughout the body, regulates body fluids
Lymphatic and Immune Systems
•Anatomy – Lymph, lymph vessels, lymph nodes, spleen, thymus,
tonsils, white blood cells
•Physiology – return proteins and fluids to the blood, carries lipids
from the GI tract, maturation and proliferation of WBCs, protects
against infection by pathogens
Respiratory System
•Anatomy – lungs
•Physiology – gas exchange between the body and the environment
Reproductive Systems
•Anatomy – gonads, associated tubes and glands, mammary glands
•Physiology – production of gametes, production of hormones,
production of milk
Digestive System
•Anatomy – organs of the gastrointestinal system, accessory organs,
and accessory glands
•Physiology – physical and chemical breakdown of macromolecules,
elimination of solid wastes
Urinary System
•Anatomy – kidneys, ureters, urinary bladder, urethra
•Physiology – produces, stores, and eliminates urine, regulates blood
volume and concentration
Body Fluids
•Intracellular fluid (ICF) – fluid within the cell
•Extracellular fluid (ECF) – the fluid outside the cell, also called
interstitial fluid
Life Processes
•Metabolism – the sum of all the chemical processes that occur in the
body.
•Dehydration synthesis – anabolic reactions
•Hydrolysis – catabolic reactions
•Responsiveness – the body’s ability to detect and respond to changes
in its internal and external environment
•Movement – motion of the whole body, individual organs, single
cells, and organelles
•Growth – an increase in the size and number of cells
•Differentiation – the process whereby unspecialized cells become
specialized cells
•Reproduction – the formation of new cells for growth, repair, and
replacement, and production of new individuals
Homeostasis: Maintaining a Stable Internal Environment
•Examples:
•Body Temperature
•37°C
•Blood Pressure
•120mmHg/80mmHg
•Blood Glucose Level
•90mg/100mL
Feedback Systems
•Feedback mechanisms – a cycle of events in which the status of a
body systems is continuously monitored, evaluated, changed,
remonitored, reevaluated, etc.
•Controlled condition – the monitored condition
•Stimulus – any disruption that causes a change in the controlled
condition
•Three components of a feedback system:
•Receptor – a body structure that monitors changes in a
controlled condition and sends input to the control center
•Control Center – the body part that receives the input from the
receptor, evaluates the input, and then sends the appropriate
output to and effector
•Effector – the body structure that receives output from the control
center and produces a response
Baroreceptors,
nociceptors,
thermoreceptors
Brain and Spinal Cord
Muscles and Glands
Pages 7
Negative Feedback Systems
•Negative feedback systems reverse a
change in the set point
•Set points controlled by negative
feedback:
•Temperature
•Blood Pressure
•Blood Glucose Level
•Water Balance
•Blood CO2 levels
Page 8
Set Point
•Homeostasis is a dynamic equilibrium, continuously moving
slightly above and then slightly below the set point. The average
of the fluctuations is the set point value
Homeostasis and Disease
•When the body remains outside of dynamic equilibrium is is said to
be in a state of disorder or disease.
•Disorder – a disturbance of structure and/or function.
•Disease – an illness characterized by a recognizable set of signs
and symptoms
•Sign – objective changes in a person that a clinician can
observe and measure:
•Bleeding, swelling, vomiting, diarrhea, fever, rash
•Symptom – subjective changes in body function that are
not apparent to an observer:
•Headache, nausea, pain
The Study of Disease
•Pathology – the science that deals with the nature, causes,
and development of abnormal conditions and the structural
and functional changes that occur from disease processes.
•Epidemiology – the science that deals with why, when, and where
diseases occur and how they are transmitted in a human community.
•Pharmacology – the science that deals with
the effects and uses of drugs in the treatment of
disease.
Aging and Homeostasis
•Aging - a process characterized by a progressive decline in the
body’s ability to restore homeostasis.
•Increases susceptibility to stress and disease
•Examples:
•Wrinkled skin, gray hair, loss of bone density, decreased
muscle mass and strength, diminished reflexes, decreases
production of hormones, increased vulnerability to disease,
infection, and cancer, decreased lung capacity, less efficient
functioning of body systems, menopause, and enlarged
prostate.
Medical Imaging
•Allows visualization of structures inside our bodies
•Radiography – a barrage of X-rays passes through the body,
producing an image of interior on X-ray sensitive film. The
image is 2-dimensional and is called an X-ray.
•Computed Tomography (CT)– formerly called computerized
axial tomography (CAT). Computer assisted radiography in
which an X-ray beam traces an arc over a section of the body
resulting in a sectional image shown on a computer screen.
Multiple images can be put together to make a 3-dimensional
picture.
CT scan
X-ray
•Digital Subtraction Angiography (DSA)– computer assisted
imaging that analyzes radiographs before and after a dye is injected
into blood vessels. Tissues around the blood vessels are erased from
the second image, leaving an unobstructed view of the blood vessels.
•Sonography – High-frequency sound waves reflect off body tissues
and are detected by the emitting wand. The resulting image, called a
sonogram, is displayed on a computer screen.
•Magnetic Resonance Imaging (MRI) – The body is exposed to a
high-energy magnetic filed, which causes protons in the body’s atoms
to arrange themselves in relation to the magnetic field. The ion
patterns are ‘read’ by a computer, which color codes the image on a
computer screen. The image can be 2- or 3-dimensional.
•Positron Emission Tomography (PET) – A substance that emits
positrons (+ charged particles) is injected into the body where it is
take up by tissues. Gamma rays are produced when these particles
collide with electrons and are detected by gamma cameras.
Sonograms
DSA
MRI
PET
Clinical Application
•Palpation – the examiner feels body surfaces with the hands.
•Pulse, chiropractic, examining lymph nodes
•Auscultation – the examiner listen to body sounds to evaluate the
function of different organs, often using a stethoscope to amplify the
sound.
•Listening to the lungs
•Percussion – the examiner taps on the body surface with the
figertips and listens to the resulting echo. Also used to reveal the size
and position of underlying structures.
•Abdominal percussion
•Autopsy – postmortem examination of the body and dissection of
its internal organs to confirm or determine the cause of death.
•Diagnosis – the science and skill of distinguishing one disorder or
disease from another.
•Dissection – the careful cutting apart of body structures to study their
relationship.
•Vivisection – the dissection of a living organism to determine the
function of the structure.
Word Roots:
-tomy = to cut
-ology = the study of
homeo- = sameness
Homeostasis – the maintenance of a
stable internal environment
Pathology – the study of disease
-stasis = standing still
patho- = disease
epi- = upon
para- = near, next to
peri- = around
cardia – heart
media- = middle
quad- = four
Pericardium – the membrane
around the heart