1. Introduction to Physiology
Chapter 1
Introduction to Physiology

2. Definition of physiology Review of organ systems Function and process
About this Chapter
Definition of physiology
Review of organ systems
Function and process
Introduction to homeostasis
Ideas in physiology
Themes in physiology
The science of physiology

3. Levels of Organization
Physiology defined
Study of the normal functioning of a living organism and its component parts
Includes all its chemical and physical processes
Literal “knowledge of nature” Aristole.
Anatomy defined
Study of structures
Literal to dissect or take apart
Organization of life
The cell is the unit of life
Cells, tissues, organs, organ systems, and organisms

4. Levels of Organization
PHYSIOLOGY
ECOLOGY
CELL
BIOLOGY
MOLECULAR
BIOLOGY
CHEMISTRY
Organ
systems
Populations of
one species
Ecosystem of
different species
Atoms
Molecules
Cells
Tissues
Organs
Organisms
Biosphere
Figure 1-1

5. Levels of Organization - Human

6. Organ Systems in Review
Protection from environmental
hazards; temperature control
Support, protection of soft
tissues; mineral storage;
blood formation
Locomotion, support, heat
production
Directing immediate responses
to stimuli, usually by coordinating
the activities of other organ
systems
Directing long-term changes
in the activities of other organ
Internal transport of cells and
dissolved materials, including
nutrients, wastes, and gases
Defense against infection and
disease
Delivery of air to sites where gas
exchange can occur between
the air and circulating blood
Processing of food and absorption
of organic nutrients, minerals,
vitamins, and water
Elimination of excess water,
salts, and waste products;
control of pH
Production of sex cells and
hormones
Organ System
Major Functions
Integumentary
system
Skeletal
Muscular
Nervous
Endocrine
Cardiovascular
Lymphatic
Respiratory
Digestive
Urinary
Reproductive
Know Names, functions and major components
NIRMCRUDLES
Integumentary
Musculoskeletal
Respiratory
Digestive
Urinary
Reproductive
Circulatory / Cardiovascular
Nervous
Endocrine
Lymphatic / Immune

7. Organ Systems in Review
The integration between systems of the body
Integumentary System
Respiratory
system
Nervous
system
Circulatory
system
Endocrine
system
Digestive
system
Musculoskeletal
system
Urinary
system
Reproductive
system
Figure 1-2

8. Function versus Process
Function explains the “why”
Teleological approach
Process or mechanism describes the “how”
Mechanistic approach
Red blood cell example
“Because cells need oxygen and red blood cells bring it to them.”
“Oxygen binds to hemoglobin molecules contained in the red blood cells.”

9. Adaptive significance of functions Keeping internal environment stable
Homeostasis
Adaptive significance of functions
Keeping internal environment stable
Cell
Intracellular fluid
Extracellular fluid
Outside world

10. the internal environment
Homeostasis
Most cells contact extracellular fluid
Out out
Out In
In in
External environment
of the body
Material enters
and leaves
the body
Material enters
and leaves
the body
Intracellular
fluid of
most cells
Extracellular fluid:
the internal environment
of the body
Figure 1-3

11. Homeostasis and Controls
External or internal change
Loss of homeostasis
Sensed by organism
Physiological attempt to correct
Negative feedback loop

12. Homeostasis and Controls
Successful compensation
Homeostasis reestablished
Failure to compensate
Illness
Death
Study of failure to compensate is pathophysiology

13. Homeostasis and Controls
Organism in
homeostasis
External
change
Internal
change
Internal change
results in
loss of homeostasis
Organism attempts
to compensate
Compensation fails
Compensation succeeds
Illness or disease
Wellness
Figure 1-4

14. Structure-function relationships
Themes in Physiology
Homeostasis
Control systems
Biological energy use
Structure-function relationships
Molecular interactions
Mechanical properties of cells, tissues, and organs
Communication
Chemical and electrical signals

15. A simple control system
Themes in Physiology
A simple control system
Input
signal
Output
signal
Controller
Figure 1-5

16. Organizational tool for relationships and processes
Concept Mapping
Organizational tool for relationships and processes
Schematic diagram of structure and function
Cells, tissues, and organs
Flow charts
Diagram processes in sequence

17. Concept Mapping: Types of Maps
Person working
outside on a hot,
dry day
Loses body water
by evaporation
Body fluids become
more concentrated
Internal receptors
sense change in
internal concentration
Thirst pathways
stimulated
Person seeks out
and drinks water
Water added
to body fluids
decreases their
concentration
(b) A process map, or flow chart
Figure 1-6b