Chapter 1:
An Introduction to the
Human Body
Copyright 2009, John Wiley & Sons, Inc.
Anatomy and Physiology Defined

Two branches of science that deal with body’s parts & function

Anatomy –
study of internal & external structures and
the physical relationship between body parts

(“what are things called?”)
 rely on observation & dissection
 Imaging techniques
Physiology The science of body functions

(“how do they work?”)
 rely on experimentation
 All specific functions are performed
by specific structures.



Structure, therefore, determines function.
Copyright 2009, John Wiley & Sons, Inc.
Branches of Anatomy

Gross or macroscopic
- surface: study of general form (morphology)
- regional: superficial and internal features in a specific body area
- systemic: structure of major organ systems

Microscopic (histology) anatomy - cytology

Developmental - from conception to physical maturity

Comparative – anatomical organization of different animals

Clinical – anatomical features that undergo changes during illness


Radiographic – structures visualized by imaging techniques
- cross-sectional
Surgical – studies landmarks important for surgery
Microscopic Anatomy
Subspecialties of Anatomy and Physiology
Copyright 2009, John Wiley & Sons, Inc.
Organism
Level
Levels of Organization
Organ System Level
Endocrine
Nervous
Cardiovascular
Lymphatic
Respiratory
Muscular
Digestive
Skeletal
Urinary
Integumentary
Reproductive
The heart
Organ
Level
Cardiac
muscle
tissue
Atoms in
combination
Tissue Level
Heart muscle cell
Complex protein
molecule
Protein filaments
Chemical or
Molecular Levels
Cellular Level
Levels of Organization

Chemical  Cellular  Tissue  Organ  Organ System 
Organism

Chemical Level: atoms  molecules

Cellular Level: smallest unit of life

Tissue Level: group of similar cells that perform a common function

Organ Level: group of 2 or more tissue types that together perform
complex physiological processes

Organ System Level: various organs with similar or related functions that
work together to accomplish a common purpose

Organismal Level- result of all simpler levels working together to sustain
life
Levels of structural organization


CHEMICAL LEVEL
 Basic level
 Atoms the smallest unit of matter
 Essential atoms for life include carbon (C), hydrogen (H),
oxygen (O), nitrogen (N), phosphorus (P), calcium (Ca),
and sulfur
 Molecules two or more atoms joined together
 Deoxyribonucleic acid (DNA)
 Glucose
CELLULAR LEVEL
 Molecules combine to form cells
 Cells are the basic structural &
functional units of an organism
 Many kinds of cells in the body
 Muscle cells, nerve cells, epithelial cells, etc.
Copyright 2009, John Wiley & Sons, Inc.
Levels of structural organization


TISSUE LEVEL
 Tissues are groups of cells and materials surrounding them
 Four basic types:
 Epithelial
 Connective
 Muscular
 Nervous
ORGAN LEVEL
 Organs are structures that are composed of two or more different
types of tissues
 Specific functions and recognizable shapes
 Examples:
 Heart, lungs, kidneys,stomach
Copyright 2009, John Wiley & Sons, Inc.
Levels of structural organization

SYSTEM LEVEL
 A system consists of related organs with a common function
 Organ-system level
 Digestive system breaks down and absorbs food
 It includes organs such as the mouth, small and large
intestines, liver, gallbladder, and pancreas
 Eleven systems of the human body

ORGANISMAL LEVEL
 An organism or any living individual
 All parts of the body functioning together
Copyright 2009, John Wiley & Sons, Inc.
LE 1-6 a,b
Hair
Skull
Epidermis &
associated
glands
Supporting bones
(scapula and clavicle)
Sternum
Ribs
Upper limb
bones
Vertebrae
Sacrum
Fingernail
Supporting
bones (hip)
Lower limb
bones
The Integumentary System
Protects against environmental hazards;
helps control body temperature
The Skeletal System
Provides support; protects tissues;
stores minerals; forms blood cells
LE 1-6 c,d
Brain
Spinal
cord
Axial
muscles
Appendicular
muscles
Peripheral
nerves
The Muscular System
Allows for locomotion; provides support;
produces heat
The Nervous System
Directs immediate responses to stimuli; usually by
coordinating the activities of other organ systems
LE 1-6 e,f
Pineal gland
Parathyroid gland
Thymus
Pituitary gland
Thyroid
gland
Heart
Suprarenal
gland
Capillaries
Pancreas
Artery
Vein
Ovary in
female
Testis in male
The Endocrine System
Directs long-term changes in
activities of other organ systems
The Cardiovascular System
Transports cells and dissolved materials,
including nutrients, wastes, and gases
LE 1-6 g,h
Thymus
Lymph nodes
Nasal cavity
Sinus
Pharynx
Trachea
Larynx
Lung
Bronchi
Diaphragm
Spleen
Lymphatic vessel
The Lymphoid System
Defends against infection and disease;
Returns tissue fluid to the bloodstream
The Respiratory System
Delivers air to sites where gas exchange can occur
between the air and circulating blood
LE 1-6 i,j
Salivary gland
Pharynx
Esophagus
Liver
Gallbladder
Stomach
Pancreas
Small intestine
Large intestine
Kidney
Urinary
bladder
Ureter
Urethra
Anus
The Digestive System
Processes food and absorbs nutrients
The Urinary System
Eliminates excess water, salts,
and waste products
LE 1-6 k,l
Prostate gland
Seminal gland
Ductus deferens
Mammary
gland
Uterine
tube
Urethra
Ovary
Uterus
Vagina
Epididymis
External
genitalia
Testis
Penis
Scrotum
The Female Reproductive System
The Male Reproductive System
Produces sex cells and hormones
Produces sex cells and hormones; supports
embryonicdevelopment from fertilization to birth
Overview of the Human Organ Systems
Integumentary
system
Protection from environmental
hazards; temperature control
Skeletal
system
Support, protection of soft tissues;
mineral storage; blood formation
Muscular
system
Locomotion, support, heat
production
Nervous
system
Directing immediate responses to
stimuli, usually by coordinating the
activities of other organ systems
Endocrine
system
Directing long-term changes
in the activities of other organ
systems
Cardiovascular
system
Internal transport of cells and
dissolved materials, including
nutrients, wastes, and gases
Lymphoid
system
Defense against infection and
disease
Respiratory
system
Delivery of air to sites where
gas exchange can occur between
the air and circulating blood
Digestive
system
Processing of food and
absorption of organic nutrients,
minerals, vitamins, and water
Urinary
system
Elimination of excess water,
salts, and waste products;
control of pH
Reproductive
system
Production of sex cells and
hormones
Clinical Connection: Noninvasive
Diagnostic Techniques

Used to assess aspects of body structure and
function

Inspection of the body to observe any changes

Palpation


Auscultation


Gently touching body surfaces with hands
listening to body sounds (stethoscope)
Percussion

Tapping on the body surface with fingertips and listening to
echoes
Copyright 2009, John Wiley & Sons, Inc.
Characteristics of Living Human
Organism

Basic Life Processes


Distinguish living from non-living things
Six important life process

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Metabolism
Responsiveness
Movement
Growth
Differentiation
Reproduction
Copyright 2009, John Wiley & Sons, Inc.
Life

Responsiveness - irritability and adaptability

Growth & Differentiation - size increase & specialization

Reproduction - new generations

Movement - internal (transport of nutrients) or external

Metabolism: complex chemical reactions to provide
energy
- catabolism: breakdown of complex molecules
- anabolism: synthesis of complex molecules

Metabolism requires absorption of materials to provide
energy
- respiration: absorption, transport, and use of O2 by cells
- excretion: elimination of waste products
Homeostasis

A condition of equilibrium (balance) in the body’s internal
environment




Dynamic condition
Narrow range is compatible with maintaining life
Example
 Blood glucose levels : 70 - 110 mg/dL
Whole body contributes to maintain homeostasis
Copyright 2009, John Wiley & Sons, Inc.
Homeostasis of Body Fluids

Delineation of fluid compartments


intracellular fluid (ICF) = within cells
extracellular fluid (ECF) = outside cells



intercellular fluid = tissue fluid = interstitial fluid
plasma = fluid portion of blood
Composition of fluids change as substances move
between compartments

nutrients, oxygen, ions and wastes move in both
directions across capillary walls
ECF and Body Location

Blood Plasma


Lymph


ECF in the brain and spinal cord
Synovial fluid


ECF within lymphatic vessels
Cerebrospinal fluid (CSF)


ECF within blood vessels
ECF in joints
Aqueous humor and vitreous body

ECF in eyes
Copyright 2009, John Wiley & Sons, Inc.
Control of Homeostasis

Homeostasis is constantly being disrupted

Physical insults


Changes in the internal environment


Drop in blood glucose due to lack of food
Physiological stress


Intense heat or lack of oxygen
Demands of work or school
Disruptions


Mild and temporary (balance is quickly restored)
Intense and Prolonged (poisoning or severe infections)
Copyright 2009, John Wiley & Sons, Inc.
Homeostasis is maintained by Feedback Systems



Receptor
 Monitors changes in a controlled condition (stimulus)
 Responds to external stimuli or internal stimuli
 Sends input to the control center
 Nerve ending of the skin in response to temperature change
Control Center (Brain)
 Sets the range of values to be maintained
 Evaluates input & generates output → Nerve impulses, hormones
Effector
 Receives output from the control center
 Produces a response or effect that changes the controlled condition
 Found in nearly every organ or tissue
 Body temperature drops the brain sends and impulse to the skeletal
muscles to contract
 Shivering to generate heat
Copyright 2009, John Wiley & Sons, Inc.
Negative and Positive Feedback systems

Negative Feedback systems

Reverses a change in a controlled condition


Regulation of blood pressure (force exerted by blood as
it presses again the walls of the blood vessels)
Positive Feedback systems

Strengthen or reinforce a change in one of the
body’s controlled conditions

Normal child birth
Copyright 2009, John Wiley & Sons, Inc.
Negative Feedback: Regulation of Blood
Pressure

External or internal stimulus
increase BP

Baroreceptors (pressure sensitive
receptors)





Detect higher BP
Send nerve impulses to brain for
interpretation
Response sent via nerve impulse
sent to heart and blood vessels
BP drops and homeostasis is
restored
Drop in BP negates the original
stimulus
Copyright 2009, John Wiley & Sons, Inc.
Positive Feedback Systems: Normal
Childbirth





Uterine contractions cause
vagina to open
Stretch-sensitive receptors in
cervix send impulse to brain
Oxytocin is released into the
blood
Contractions enhanced and
baby pushes farther down the
uterus
Cycle continues to the birth of
the baby (no stretching)
Copyright 2009, John Wiley & Sons, Inc.
Homeostatic Imbalances

Normal equilibrium of body processes are
disrupted

Moderate imbalance





Disorder or abnormality of structure and function
Disease specific for an illness with recognizable signs
and symptoms
Signs are objective changes such as a fever or swelling
Symptoms are subjective changes such as headache
Severe imbalance

Death
Copyright 2009, John Wiley & Sons, Inc.
Homeostatic Imbalances:
Areas of Science

Epidemiology



Occurrence of diseases
Transmission in a community
Pharmacology


Effects and uses of drugs
Treatment of disease
Copyright 2009, John Wiley & Sons, Inc.
Clinical Connection: Autopsy


Postmortem (after death) examination of the
body and internal organs
Several uses:




Determine the cause of death
Identify diseases not detected during life
Determine the extent of injuries and contribution
to death
Hereditary conditions
Copyright 2009, John Wiley & Sons, Inc.
Clinical Connection: Diagnosis of Disease

Distinguishing one disorder or disease from
another


Signs and symptoms
Medical history



Collecting information about event
Present illnesses and past medical problems
Physical examination


Orderly evaluation of the body and its function
Noninvasive techniques and other vital signs (pulse)
Copyright 2009, John Wiley & Sons, Inc.
Basic Anatomical Terminology


Common language referring to body
structures and their functions
Anatomists use standard anatomical position
and special vocabulary in relating body parts
Copyright 2009, John Wiley & Sons, Inc.
The Language of Anatomy
The Anatomical
Position










Body upright
Standing erect facing the
observer
Head and eyes facing
forward
Feet are flat on the floor and
forward
Upper limbs to the sides
Palms turned forward
Prone position:
Body is lying face down
Supine position:
Body is lying face up
1.3
Anatomical Landmarks
Frons or
forehead (frontal)
Nasus or nose (nasal)
Oculus or
eye (orbital or ocular)
Cranium
or skull
(cranial)
Cephalon
or head
(cephalic)
Oris or mouth (oral)
Mentis or chin
(mental)
Axilla or armpit
(axillary)
Brachium
or arm
(brachial)
Antecubitis
or front of
elbow
(antecubital)
Facies
or face
(facial)
Auris or
ear (otic)
Bucca or
cheek (buccal)
Cervicis or neck (cervical)
Thoracis or
thorax, chest
(thoracic)
Mamma
or breast
(mammary)
Trunk
Abdomen
(abdominal)
Umbilicus
or navel
(umbilical)
LE 1-8a
Antebrachium
or forearm
(antebrachial)
Carpus
or wrist (carpal)
Pelvis
(pelvic)
Manus
or hand
(manual)
Palma
or palm
(palmar)
Digits (phalanges)
or fingers (digital
or phalangeal)
Pollex
or thumb
Patella
or kneecap
(patellar)
Crus or
leg (crural)
Inguen
or groin
(inguinal)
Pubis
(pubic)
Femur or
thigh (femoral)
Tarsus or
ankle
tarsal)
Digits (phalanges)
or toes (digital or
phalangeal)
Hallux or
great toe
Pes
or foot
(pedal)
LE 1-8a
LE 1-8b_1
Shoulder
(acromial)
Dorsum or
back
(dorsal)
Olecranon
or back
of elbow
(olecranal)
Lumbus
or loin
(lumbar)
Cephalon or
head (cephalic)
Cervicis or
neck (cervical)
Upper
limb
LE 1-8b_2
Gluteus
or buttock
(gluteal)
Popliteus or
back of knee
(popliteal)
Sura or
calf (sural)
Calcaneus or
heel of foot
(calcaneal)
Planta or
sole of foot (plantar)
Lower
limb
Directional Terms
Copyright 2009, John Wiley & Sons, Inc.
Cranial
Right
Left
Proximal
Posterior
or dorsal
Anterior
or ventral
Lateral
Caudal
Medial
Proximal
Distal
Distal
LE 1-10
Abdominopelvic Quadrants
Right lobe of liver,
gallbladder, right kidney,
portions of stomach, small
and large intestine
Cecum, appendix, and
portions of small intestine,
reproductive organs (right
ovary in female and right
spermatic cord in male),
and right ureter
Left lobe of liver, stomach,
pancreas, left kidney,
spleen, portions of large
intestine
Most of small intestine,
and portions of large
intestine, left ureter, and
reproductive organs (left
ovary in female and left
spermatic cord in male)
Abdominopelvic Regions
Right
hypochondriac
region
Right lumbar
region
Right inguinal
region
Epigastric
region
Umbilical
region
Hypogastric
region
Left
hypochondriac
region
Left lumbar
region
Left inguinal
region
LE 1-9b
Superficial anatomical landmarks and
underlying organs
Stomach
Liver
Spleen
Gallbladder
Large intestine
Small intestine
Appendix
Urinary
bladder
LE 1-9c

R. Hypochondriac - right, upper 1/3; gallbladder, liver, r. kidney

Epigastric - Upper, central 1/3; liver, stomach, pancreas, duodenum

L. Hypochondriac - left, upper 1/3; spleen, colon, liver, l. kidney, small
intestine

R. Lumbar - right, lateral 1/3; cecum, ascending colon, liver, r. kidney,
small intestine

Umbilical - center; umbilicus (navel) is located here; jejunum, ileum,
duodenum, colon, kidneys, major abdominal vessels

L. Lumbar - left, lateral 1/3; descending colon, l. kidney, small intestine

R. Iliac (inguinal) - right, lower 1/3; appendix, cecum, small intestine

Hypogastric (pubic) - lower, center 1/3; urinary bladder, small intestine,
sigmoid colon, female reproductive organs

L. Iliac (inguinal) - left, lower 1/3; small intestine, descending colon,
sigmoid colon
Planes and Sections

Imaginary flat surfaces
that pass through the
body parts

Sagittal plane

A vertical plane that divides
the body into right and left
sides


Midsagittal plane divides
body into equal right and
left sides
Parasagittal plane divides
body into unequal right and
left sides
Copyright 2009, John Wiley & Sons, Inc.
Planes and Sections

Frontal or coronal plane


Divides the body or an organ into anterior (front)
and posterior (back) portions
Transverse plane


Divides the body or an organ into superior (upper)
and inferior (lower) portions
Also called cross-sectional or horizontal plane
Copyright 2009, John Wiley & Sons, Inc.
Planes of Section
Frontal plane
Sagittal plane
Transverse plane
LE 1-11
Planes and Sections

Oblique plane

Passes through the body
or an organ at an angle



Between transverse and
sagittal plane
Between transverse and
frontal plane
Sections

Cut of the body made
along a plane
Copyright 2009, John Wiley & Sons, Inc.
Body Cavities

Spaces within the body that help protect,
separate, and support internal organs



Cranial cavity – dorsally located
Thoracic cavity – ventrally located
Abdominopelvic cavity – ventrally located
Copyright 2009, John Wiley & Sons, Inc.
Copyright 2009, John Wiley & Sons, Inc.
Cranial Cavity and Vertebral Canal

Cranial cavity

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
Vertebral canal



Formed by the cranial bones
Protects the brain
Formed by bones of vertebral
column
Contains the spinal cord
Meninges

Layers of protective tissue that
line the cranial cavity and
vertebral canal
Copyright 2009, John Wiley & Sons, Inc.
LE 1-14
Provides protection;
allows organ movement;
lining prevents friction
separated by
diaphragm into
Surrounds
right lung
Surrounded by chest
wall and diaphragm
Contains the
peritoneal cavity
subdivided into
Includes the
Contains the trachea,
esophagus, and
major vessels
also contains
Surrounds heart
Surrounds
left lung
Contains many
digestive glands
and organs
Contains urinary
bladder,
reproductive organs,
last portion
of digestive tract
Thoracic Cavity


Also called the chest
cavity
Formed by




Ribs
Muscles of the chest
Sternum (breastbone)
Vertebral column (thoracic
portion)
Copyright 2009, John Wiley & Sons, Inc.
Thoracic Cavity

Within the thoracic
cavity

Pericardial cavity


Fluid-filled space that
surround the heart
Pleural cavity

Two fluid-filled spaces that
that surround each lung
Copyright 2009, John Wiley & Sons, Inc.
Thoracic Cavity

Mediastinum

Central part of the
thoracic cavity



Between lungs
Extending from the sternum
to the vertebral column
First rib to the diaphragm

Diaphragm
 Dome shaped muscle
 Separates the thoracic
cavity from the
abdominopelvic cavity
Copyright 2009, John Wiley & Sons, Inc.
Abdominopelvic Cavity



Extends from the diaphragm to the groin
Encircled by the abdominal wall and bones
and muscles of the pelvis
Divided into two portions:

Abdominal cavity


Stomach, spleen, liver, gallbladder, small and large
intestines
Pelvic cavity

Urinary bladder, internal organs of reproductive system,
and portions of the large intestine
Copyright 2009, John Wiley & Sons, Inc.
Serous Cavities
• Serous cavity – narrow fluid-filled space lined by a serous
membrane (serosa)
- Pleura
- Pericardium
- Peritoneum
• Parietal serosa – pleura covers the opposing mediastinal surface
and inner body wall; pericardium is continuous with the viseral
serosa; peritoneum lines the body wall
• Visceral serosa – covers the visceral organs
• Serous Fluid – watery lubricant secreted by both serous
membranes to minimize friction between organs and cavity walls
• Mesenteries – organs (stomach, small intestine, parts of large
intestine) are suspended by double sheets of peritoneum to
provide support and stability with limited movement
Thoracic and Abdominal Cavity
Membranes

Viscera

Organs of the thoracic and
abdominal pelvic cavities


Serous membrane is a thin
slippery membrane that covers
the viscera
Parts of the serous membrane:


Parietal layer

Lines the wall of the cavities
Visceral layer

Covers the viscera within the
cavities
Copyright 2009, John Wiley & Sons, Inc.
Thoracic and Abdominal Cavity
Membranes
Copyright 2009, John Wiley & Sons, Inc.
Thoracic and Abdominal Cavity
Membranes

Pleura

Serous membrane of the pleural cavities



Pericardium

Serous membrane of the pericardial cavity



Visceral pleura clings to surface of lungs
Parietal pleura lines the chest wall
Visceral pericardium covers the heart
Parietal pericardium lines the chest wall
Peritoneum

Serous membrane of the abdominal cavity


Visceral peritoneum covers the abdominal organs
Parietal peritoneum lines the abdominal wall
Copyright 2009, John Wiley & Sons, Inc.
Serous Cavities
Visceral
pericardium
Heart
Pleural
cavity
Pericardial
cavity
Thoracic
cavity
Pericardial
cavity
Pleural
cavity
Parietal
pericardium
Pericardial
cavity
Diaphragm
Air space
Diaphragm
Peritoneal
cavity
Abdominal
cavity
Balloon
Abdominal
cavity
Abdominopelvic
cavity
Pelvic
cavity
Pelvic cavity
Sternum
Heart in
pericardial
cavity
Pleural cavity
Right
lung
Left
lung
Pleura
Right
lung
Left
lung
Mediastinum
Spinal cord
LE 1-13
Other Cavities

Oral (mouth) cavity

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Nasal cavity


eyeball
Middle ear cavities


nose
Orbital cavities


Tongue and teeth
Small bones of the middle ear
Synovial cavities

Joints
Copyright 2009, John Wiley & Sons, Inc.
Medical Imaging

Techniques and procedures used to create
images of the human body



Allow visualization of structures inside the body
Diagnosis of anatomical and physiological
disorders
Conventional radiography (X-rays) have been in
use since the late 1940’s
Copyright 2009, John Wiley & Sons, Inc.
Radiography (insert figures for each image
in following slides)

X-rays




produce image of interior structures
Inexpensive and quick
Hollow structures appear black or
gray
Do not pass easily through dense
structure (bone)

At low dose, useful for soft tissue
(breast)


Mammography (breast)
Bone densitometry (bone density)
Copyright 2009, John Wiley & Sons, Inc.
Magnetic Resonance Imaging (MRI)

High energy magnetic field


Color image on a video
monitor


2D and 3D blueprint
Relatively safe procedure


Protons in body fluid align with
field
Not used on patients containing
metal
Used for differentiating
normal and abnormal tissues

Tumors, brain abnormalities,
blood flow
Copyright 2009, John Wiley & Sons, Inc.
Computed Tomography

Computer-Assisted
radiography (CT-Scan)




3-D structures
Visualize soft tissue in more
detail than conventional
radiography
Tissue intensities show
varying degrees of gray
Whole-body CT scan

Lung and kidney cancers,
coronary artery disease
Copyright 2009, John Wiley & Sons, Inc.
Ultrasound Scanning

Ultrasound Scanning

High frequency sound waves



Sonogram
Noninvasive, painless, no dyes
Pregnancy (fetus)
Copyright 2009, John Wiley & Sons, Inc.
Radionuclide Scanning

Radionuclide Scanning




Radioactive substance
(radionuclide) given intravenously
Gamma rays detected by camera
Radionuclide image displays on
video monitor
Color intensity represents uptake

Single-photo-emission computerized
tomography (SPECT)
 Specialized technique used for
brain, heart, lungs, and liver
Copyright 2009, John Wiley & Sons, Inc.
Positron Emission Tomography (PET)

Positron (positively charged
particles) emitting substance
injected into the body




Collision between positrons and
negatively charged electron in
body tissues
Gamma rays produced
Computer constructed a PET
scan image in color
Used to study physiology of
body structures (metabolism)
Copyright 2009, John Wiley & Sons, Inc.
Endoscopy

Endoscope



Colonoscopy


Interior of colon
Laparoscopy


Lighted instrument with lens
Image projected onto a monitor
Organs in abdominopelvic cavity
Arthroscopy

Interior of joint (knee)
Copyright 2009, John Wiley & Sons, Inc.