Anatomy
 Study of the structure and
shape of the body and its
parts
Physiology
 Study of how the body
and its parts work or
function
 Gross anatomy
 Large structures
 Easily observable
Figure 14.1
 Microscopic Anatomy
 Very small
structures
 Can only be
viewed with
a microscope
Figure 14.4c–d
 Atoms
 Molecules
 Macromolecules
 Organelles
 Cells
 Tissues
 Organs
 Organ Systems
 Organism
 Integumentary
 Cardiovascular
 Skeletal
 Lymphatic
 Muscular
 Digestive
 Nervous
 Respiratory
 Endocrine
 Urinary
 Reproductive (male &
female)
 Integumentary
 Forms the external body
covering
 Protects deeper tissue from
injury
 Helps regulate body
temperature
 Location of cutaneous
nerve receptors
Figure 1.2a
 Skeletal
 Protects and supports
body organs
 Provides muscle
attachment for movement
 Site of blood cell
formation
 Stores minerals
Figure 1.2b
 Muscular
 Produces movement
 Maintains posture
 Produces heat
Figure 1.2c
 Nervous
 Fast-acting control
system
 Responds to internal and
external change
 Activates muscles and
glands
Figure 1.2d
 Endocrine
 Secretes regulatory
hormones
 Growth
 Reproduction
 Metabolism
Figure 1.2e
 Cardiovascular
 Transports materials in body via
blood pumped by heart
 Oxygen
 Carbon dioxide
 Nutrients
 Wastes
Figure 1.2f
 Lymphatic
 Returns fluids to blood
vessels
 Cleanses the blood
 Involved in immunity
Figure 1.2g
 Respiratory
 Keeps blood supplied with
oxygen
 Removes carbon dioxide
Figure 1.2h
 Digestive
 Breaks down food
 Allows for nutrient
absorption into blood
 Eliminates indigestible
material
Figure 1.2i
 Urinary
 Eliminates nitrogenous wastes
 Maintains acid-base balance
 Regulates water and
electrolytes
Figure 1.2j
 Reproductive
 Produces
offspring
Figure 1.2k–l
 Maintain boundaries
 Movement
 Locomotion
 Movement of substances
 Responsiveness
 Ability to sense changes
and react
 Break-down and
absorption of nutrients
 Metabolism—chemical
reactions within the body
 Produces energy
 Makes body structures
 Excretion
 Eliminates waste from
metabolic reactions
 Reproduction
 Produces future
generation
 Growth
 Increases cell size and
number of cells
 Nutrients
 Chemicals for energy and
cell building
 Includes carbohydrates,
proteins, lipids, vitamins,
and minerals
 Oxygen
 Required for chemical
reactions
 Water
 60–80% of body weight
 Provides for metabolic reaction
 Stable body temperature
 Atmospheric pressure
 Must be appropriate
Figure 1.3
 Homeostasis—maintenance of a stable internal
environment
 A dynamic state of equilibrium
 Homeostasis is necessary for normal body
functioning and to sustain life
 Homeostatic imbalance
 A disturbance in homeostasis resulting in disease
Input:
Information
sent along
afferent
pathway to
Control
center
Output:
Information sent
along efferent
pathway to activate
Effector
Receptor (sensor)
Change
detected
by receptor
Stimulus:
Produces
change
Variable
in variable
(in homeostasis)
Response of
effector feeds
back to
influence
magnitude of
stimulus and
returns variable
to homeostasis
Figure 1.4
Variable
(in homeostasis)
Figure 1.4, step 1a
Stimulus:
Produces
change
Variable
in variable
(in homeostasis)
Figure 1.4, step 1b
Receptor (sensor)
Change
detected
by receptor
Stimulus:
Produces
change
Variable
in variable
(in homeostasis)
Figure 1.4, step 2
Input:
Information
sent along
afferent
pathway to
Control
center
Receptor (sensor)
Change
detected
by receptor
Stimulus:
Produces
change
Variable
in variable
(in homeostasis)
Figure 1.4, step 3
Input:
Information
sent along
afferent
pathway to
Control
center
Output:
Information sent
along efferent
pathway to activate
Effector
Receptor (sensor)
Change
detected
by receptor
Stimulus:
Produces
change
Variable
in variable
(in homeostasis)
Figure 1.4, step 4
Input:
Information
sent along
afferent
pathway to
Control
center
Output:
Information sent
along efferent
pathway to activate
Effector
Receptor (sensor)
Change
detected
by receptor
Stimulus:
Produces
change
Variable
in variable
(in homeostasis)
Response of
effector feeds
back to
influence
magnitude of
stimulus and
returns variable
to homeostasis
Figure 1.4, step 5
 The body communicates
through neural and
hormonal control systems
 Receptor
 Responds to changes in the
environment (stimuli)
 Sends information to
control center
 Control center
 Determines set point
 Analyzes information
 Determines appropriate
response
 Effector
 Provides a means for
response to the stimulus
 a muscle contracting to
move the arm
 a muscle squeezing saliva
from the salivary gland
 a gland releasing a hormone
into the blood
 The purpose of organ systems is to provide an




organism with a stable internal environment.
Injury and illness disrupt this internal balance.
The body remains in homeostasis by a system
called negative feedback.
The negative feedback loop is the MOST common.
Human and Animal medicine attempts to regain
homeostasis within particular systems which
cannot regain balance due to illness and injury.
 A positive feedback mechanism is the exact opposite
of a negative feedback mechanism. With negative
feedback, the output reduces the original effect of the
stimulus. In a positive feedback system, the output
enhances the original stimulus
 Examples: Child birth (production of Oxytocin to
cause contractions) and blood clotting
 Just remember that positive feedback mechanisms
enhance the original stimulus and negative feedback
mechanisms inhibit it.
 Special terminology is used to prevent
misunderstanding
 Exact terms are used for
 Position
 Direction
 Regions
 Structures
 Anatomical Position – a standard body position
for studying the body—standing erect with arms at
your side and palms facing ventral
Table 1.1 (1 of 3)
Table 1.1 (2 of 3)
Table 1.1 (3 of 3)
 Superior
 Proximal
 Inferior
 Distal
 Ventral
 Superficial
 Dorsal
 Deep
 Medial
 Lateral
 A median (sagittal) section divides the body (or
organ) into equal left and right parts
 A frontal (coronal) section divides the body (or
organ) into anterior and posterior parts
 A transverse (cross) section divides the body (or
organ) into superior and inferior parts
 Dorsal body cavity
 Cranial cavity houses the brain
 Spinal cavity houses the spinal cord
 Ventral body cavity
 Thoracic cavity houses heart, lungs and others
 Abdominopelvic cavity houses digestive system and
most urinary system organs
(pleural cavity)
Figure 1.8c
 Serous membranes line the
walls of cavities and cover
organs.
 These membranes secrete
serous fluid which lubricate
the free surfaces.