CHAPTER 1
AN INTRODUCTION TO
ANATOMY &
PHYSIOLOGY
Pictures from Essentials of Anatomy & Physiology, Third Edition
I. Introduction (basic functions of
all living things)
A.
Responsiveness – immediate (irritability), long
term changes (adaptability). Important for the basis
of homeostasis (maintaining balance)
B. Growth (organism gets larger through increase in
cells)
C. Reproduction
D. Movement –
internal (transporting food or blood)
external (locomotion)
E. Metabolism – all the chem rxs in the body
Catabolic rxs – break down
Anabolic rxs – build up
II. The Sciences of Anatomy and
Physiology
Anatomy – internal & external structure
 Physiology – function of the structure
 If you change the structure it no longer
performs its original function
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A. Microscopic Anatomy (structures not
seen w/o magnification)
Cytology – analyzes the internal structures of
cells – cell biology
 Histology – examines tissues
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B. Gross Anatomy (macroscopic-visible with
unaided eye)
Surface anatomy – general form & superficial
markings
 Regional anatomy – superficial & internal
features of a specific region
 Systemic anatomy – structure of major organ
systems
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C. Physiology
Cell Physiology – functions of cells & chem
processes
 Special Physiology – specific organs (kidney,
heart)
 System Physiology – all aspects of an organ
system (respiratory, excretory)
 Pathological Physiology – effects of diseases
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III. Levels of Organization
Changes at the lowest level affect the whole
organism!!
A. Chemical or Molecular Level – atoms &
molecules, shape is important
B. Cellular Level – smallest living unit,
organelles have specific functions
C. Tissue Level – similar cells performing a
specific function
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D. Organ Level – 2 or more tissues together to
perform a specific function
E. Organ System Level – all the structures that
make the organ function – heart, blood vessels,
blood
F. Organism Level – all organs working together
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Damage to 1 level can affect another level –
blood loss
IV. An Introduction to Organ Systems
- know the major functions of each.
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A. Integumentary
B. Skeletal
C. Muscular
D. Nervous
E. Endocrine
F. Cardiovascular
G. Lymphatic
H. Respiratory
I. Digestive
J. Urinary
K. Male Reproductive
L. Female Reproductive
Protects, maintains body temp
Support, protects tissues,
stores mineral, forms blood
Locomotion, provides
support, produces heat
Directs immediate response to
stimuli, coordinates activities of
other organ systems
Directs long term changes in
activities of other organ
systems
Transports cells & dissolved
materials (nutrients, wastes,
gases)
Defends against infection &
disease, returns tissue fluid to
bloodstream
Delivers air to sites where
gas exchange occurs
between air & blood
Processes food & absorbs
nutrients
Eliminates excess water, salt,
waste products
Produce sperm & hormones
Produce eggs & hormones
V. Homeostasis and System
Integration
We are never physiologically in a state of
“unchanging sameness” – unless you’re dead!
A. Homeostatic Regulation
 Responses to stimulus to maintain our stable
internal environment (or adjustments in
physiological systems to preserve homeostasis)
 Receptor (sensitive to stimulus), Control Center
(receives & processes info), Effector (responds
to stimulus)
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Operates like a thermostat – heater turns
on if room becomes cold (winter) and the
AC turns on if the room becomes to hot
(summer)
Negative Feedback
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A variation outside normal limits triggers an
automatic response that corrects the situation
Effector that is activated by the control center
opposes or eliminates the stimulus
Most mechanisms in body operate this way
Example: thermoregulation (body temp)
Negative feedback
Negative feedback
Positive Feedback Loop
Initial stimulus produces a response that
reinforces the stimulus
 Important in accelerating processes that
must proceed to completion quickly
 Example: blood clotting (releases
chemicals that accelerate the process until
bleeding stops)
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Positive feedback
Homeostasis & Disease
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When homeostatic regulation fails, organ
systems malfunction and the individual
experiences illness or disease
VI. The Language of Anatomy
A. Surface Anatomy
 Anatomical Landmarks - refer to Fig. 1-5.
Know only those terms in bold type.
– face up
 Prone – face down
 Supine
Anatomical landmarks
Anatomical landmarks
Anatomical Regions – refer to Table 1-1.
 Anatomical Directions - refer to Fig. 1-7 and
the directional references diagram at end of
notes. Best to study in pairs. Know
directions and Table 1-2.
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Directional
references
B. Sectional Anatomy
 Planes and Sections - refer to planes of section
diagram at end of notes. Know.
– superior & inferior pieces
 Frontal – anterior & posterior pieces
 Sagittal – right & left pieces
 Transverse
Planes of sections
Body Cavities
(2 functions)
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 Protect
organs (brain, spine)
 Permit significant changes in size & shape of
visceral organs (heart, lungs, stomach)
Lined with serosal membranes that secrete
serosal fluid
Dorsal Body Cavities
Cranial - encloses brain
Spinal – surrounds spinal cord
Ventral Body Cavities
Most organs are surrounded by moist internal spaces
that allow for expansion but prevent friction