Organization of the Human
Body
ST110
CONCORDE CAREER COLLEGE, PORTLAND
Objectives
 Define the terms anatomy, physiology, and
pathology
 Identify the structural units of the body from the
chemical level to the organ systems
 Define chemistry as it relates to cell function
 List the organ systems and the major structures of
each system
Objectives
 List and define the terms of direction
 Apply the terms of direction to the body
 List and define the body planes
 Apply body plane terminology when referencing
the body
 List and identify the body cavities and the organ(s)
contained within each cavity
Terms
 Anatomy
Study of structures of
the body
 Physiology
Study of functions of
structures of the body
 Pathophysiology
Study of diseases and
disorders
History of Anatomy and Physiology
 Imhotep, 2650-2600 BC: recorded some of the
earliest information on surgery
 Aristotle, 384-322 BC: founder of comparative
anatomy
 Herophilos, 335-280 BC: “The First Anatomist,”
described the diagnostic value of the pulse
 Erasistratus, 304-250 BC: contributed to the
understanding of the anatomy of the brain, and
noted the difference between motor and sensory
nerves
History of Anatomy and Physiology
 Galen, year 129-200 AD: “First Great Anatomist,”
his writings remained unchallenged for 1,500 years.
Conformed his anatomic findings to theological
principles
 Andreas Vesalius, 1514-1564: “Father of Modern
Anatomy,” corrected Galen’s mistakes. Dissected
human cadavers.
 Ambroise Pare, 1510-1590: “Greatest Surgeon of
the 16th century,” first to ligate vessels to control
bleeding after amputations .
Organization of the Human Body
 The levels of organization progress from the least
complex (chemical level) to the most complex
(organism level)
 Atoms and molecules are referred to as the chemical
level
Organization of the Human Body
 Cells are the smallest living units of structure and
function in our body.
 Tissues are an organization of many similar cells .
 Organs are an organization of several different kinds
of tissues.
Organization of the Human Body
 Systems are varying numbers and kinds of organs
working together to perform complex functions.
 The body is a unified and complex assembly of
interactive components.
Anatomical Position
 When a person is in anatomical position, the
body is erect and facing forward with arms supinated
at the side and palms of the hands and feet facing
forward.
 Supine- face up, palms up
 Prone- face down, palms down
Anatomical Position
Positions
Directional Terms
 Superior/cephalic Inferior/caudal Anterior/ventral Posterior/dorsal-
 Medial Lateral Proximal-
above, the very top
below, very low
toward the front
toward the back
most near the imaginary
midline
away from the midline
closest to the point of
attachment Distal-away from
the point of attachment
Directional Terms
 Superior – toward the head
 Inferior – toward the feet
 Anterior – front
 Posterior – back
 Adduct – bring near
 Abduct – move away
Directional Terms
 Medial – toward the midline of the body
 Lateral – toward the side of the body
 Proximal – nearest the point of origin of one of its parts
 Distal – away from the point of origin
 Varus – turned inward
 Valgus – turned outward
 Flexion – bend a joint
 Extension – extend a joint
 Dorsiflexion – turn the foot up
 Plantar flexion – turn the foot down
 Rotation – internal/external
 Circumduction – circular joint movement
Directional Terms
 Contralateral – opposite side
 Ipsilateral – same side
 Equilateral – the same on both sides
 Dorsal – toward the posterior surface
 Ventral – toward the anterior surface
 Volar – pertaining to the palm or sole
Terms of Reference
 Deep Superficial Internal External-
 Central Peripheral Visceral-
away from the surface
near the surface
inside
outside
closer to the inside or within a
system
closer to the outside or on the
outside
pertaining to the covering of the
internal organs
Geometric Planes
Geometric Planes
 The body is sectioned into imaginary geometric
planes:





Sagittal - divides the body or parts into right and left sides
Midsagittal (median plane)– divides the body into equal
right and left sides
Transverse (horizontal plane)- divides the body or parts into
upper and lower portions
Coronal (frontal plane)- divides the body or parts into
anterior and posterior portions
Cross section – a transverse cut that is at angles to the long
axis of the organ
Sagittal
Transverse
Coronal
Quadrants
 When making clinical diagnoses surgeons frequently
use quadrants to indicate the area of bodily pain
 RUQ – right upper quadrant
 RLQ – right lower quadrant
 LUQ – left upper quadrant
 LLQ – left lower quadrant
Quadrants
Nine Regions
 Two sagittal planes and two transverse planes divide
the abdomen into nine regions









Right Hypochondrium
Left Hypochondrium
Epigastrium
Right Lumbar
Left lumbar
Umbilical
Right Iliac
Left Iliac
Hypogastrium
Nine Regions
Major Body Cavities
 The body is divided into two major cavities:
 Dorsal Cavity – Posterior division of the body,
further subdivided into the cranial cavity and the
spinal cavity
 Ventral Cavity – Anterior division of the body,
further subdivided into the thoracic and
abdominopelvic cavities


Pleura- contains the lungs
Abdominal- contains the liver
Body Cavities
Body Cavities
Body Cavities
Cranial cavity: contains the brain
Spinal Cavity: contains the spinal cord
The membranes that line the cranial and spinal cavities are
called the meninges
Body Cavities
Thoracic cavity: further subdivided into the…
 mediastinum: esophagus, thymus gland, trachea, heart, great
vessels

Pericardial cavity: contains the heart (within its pericardial sac)
Pleural cavities: contains the lungs
Abdominopelvic cavity: also called the peritoneal cavity is
further subdivided into the…
 Abdominal cavity: contains the stomach, liver, gallbladder,
spleen, pancreas, small intestines, and colon
 Pelvic cavity: sigmoid colon, rectum, bladder, and internal
reproductive organs

Diaphragm
 Separates the thoracic cavity from the
abdominopelvic cavity
 Is the most important muscle in breathing
Diaphragm
Peritoneum
 The peritoneum is a serous membrane that lines the
abdominal cavity



Parietal peritoneum: lines the wall of the abdominopelvic
cavity
Visceral peritoneum: covers the organs in the
abdominopelvic cavity
Peritoneal space: small space between the two layers,
contains serous fluid and reduces friction
Mesentery
 Mesentery: a fold of peritoneum that invests the
intestines and attaches them to the posterior
abdominal wall
 Omentum : a double fold of peritoneum that is
divided into the greater omentum and the lesser
omentum


Greater omentum: attaches to the greater curvature of the
stomach and hangs loosely downward covering the intestines
Attaches to the lesser curvature of the stomach and duodenum
Body Systems
Body Systems
 A group of organs arranged to perform a more complex
function
 There are 11 major organ systems in the human body
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Integumentary
Skeletal
Muscular
Nervous
Endocrine
Circulatory (cardiovascular & peripheral vascular)
Lymphatic
Digestive
Respiratory
Urinary
Reproductive
Integumentary system
Largest organ system which Includes:
•Skin
•Sweat glands
•Sebaceous glands
•Hair
•Nails
Skeletal System
Includes:
•Skeleton
•Ligaments
•Tendons
•Cartilage
Muscular System
Includes:
•Skeletal muscle (Voluntary/striated muscle)
•Smooth muscle (involuntary/non striated muscle)
•Cardiac muscle
Nervous system
Includes:
•Brain
•Spinal cord
•Cranial nerves
•Peripheral nerves
Nervous System cont.
 CNS – Central nervous system, consists of the brain
and spinal cord
 PNS – Peripheral nervous system, comprises the
nerves
Endocrine system
Includes:
•Pituitary gland (master gland)
•Thyroid gland
•Parathyroid gland
•Pancreas
•Thymus gland
•Adrenal glands
•Testes
•Ovaries
Circulatory system
Includes:
•Cardiovascular system
•Heart, coronary arteries,
aorta, pulmonary arteries and
veins, superior and inferior
vena cava
•Peripheral vascular system
•all arteries, veins and
capillaries outside of the heart
Lymphatic system
Includes:
•Lymph fluid
•Lymph vessels
•Lymph nodes
•Spleen
•Thymus
Digestive system
Includes:
•Mouth
•Teeth
•Tongue
•Salivary
glands
•Pharynx
•Esophagus
•Stomach
•Liver
•Gallbladder
•Biliary duct system
•Pancreas
•Small intestine
•colon
Respiratory system
Includes:
•Nasal cavity
•Pharynx (throat)
•Larynx (voice box)
•Trachea (wind pipe)
•Lungs
•Bronchi
•Bronchioles
•Alveoli
Genitourinary system
Includes:
•Kidneys
•Ureters
•Urinary bladder
•Urethra
Female Reproductive System
Includes:
•Ovaries
•Fallopian tubes
•Uterus
•Vagina
•Clitoris
•External genitalia (vulva)
•Breast
Male Reproductive system
Includes:
 Scrotum
 Testes
 Epididymis
 Vas deferens
 Seminal vesicles
 Prostate gland
 Bulbourethral glands
 Urethra
 penis
Metabolism
 Life-sustaining reactions that go on within the body
systems

Catabolism-complex substances are broken down to simpler
compounds. Breakdown of nutrients


ATP-energy obtained from the breakdown
Anabolism-simple compounds used to manufacture materials
for growth, function and repair
Fluid Balance
 Extracellular fluid- all fluids outside the cells
 Intracellular fluid-all fluids within the cells
Homeostasis
 Homeostasis: is the coordination of all the various
functions of the body to maintain a normal internal
environment. (consistency)

Negative feedback-monitoring internal conditions and
bringing them back to normal
Review
 What is the smallest level of organization in the
human body?
chemical
Review
 What is the smallest structural unit in the body?
cells
Review
 Describe anatomical position.
Body is erect, standing with arms at sides, palms
turned forward, head and feet forward
Review
 What is “toward the midline of the body?”
medial
 What is “nearer the surface?”
superficial
 What is “back”
posterior
Review
 Which plane divides the body into front and back
portions?
Frontal/coronal
 Which plane divides the body into right and left
sides?
Sagittal
Review
 Which subcavities are contained in the dorsal cavity?
Cranial, Spinal
 Which subcavities are contained in the ventral
cavity?
Thoracic, pleural, abdominopelvic