Chapter 1
The Study of Body Function
“To treat disease and injury appropriately, we must first understand the human body in its healthy state.”

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Chapter 1 Outline
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Scientific Method
Homeostasis
Organ systems
Function and process
Ideas in physiology
Themes in physiology
The science of physiology
Discussion of scientific literature
Organs & Systems
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Human Physiology
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Physiology: ‘knowledge of nature’
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Pathophysiology:
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study of how body works to maintain life
“Normal functioning of a living organism and its component parts, including all its chemical and physical processes.” emphasis is on cause and effect mechanisms

how physiological processes are altered in disease or injury Comparative Physiology:
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comparing other vertebrates and invertebrates
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Physiological Systems
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Organization of life
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The cell is the basic unit of life

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Cells, tissues, organs, organ systems, and organisms

Histology =Microscopic study of tissues
Primary tissues include muscle, nervous, epithelial, connective

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Organs
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Are anatomical & functional units made of 2 or more primary tissues

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Systems are groups of organs working together to maintain homeostasis
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Nervous & Endocrine System
Musculoskeletal System
Circulatory System
Respiratory System
Immune System
Urinary System
Digestive System
Reproductive System
Integumentary System

(see Table 1.1)

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Fig. 1-2

Function & Process
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Physiology integrates function and process! Why (Teleological) and How
(Mechanistic)
Form Fits Function
Emergent Properties=Whole is greater than the sum of its’ parts

Homeostasis

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Homeostasis
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Maintenance of fairly constant internal conditions  Around physiological set points
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Maintained primarily by feedback loops
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Continuous ongoing processes
 Insulin & glucose levels
 Blood volume/pressure
 Body temperature

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Feedback Loops
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Sensor:

Detects deviation from set point
(input signal)
Integrating center:
Determines response
(controller)
Effector:
Produces
response
(output signal)

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Negative Feedback Hormonal
Control of Blood Glucose

Fig 1.6
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Positive Feedback Systems
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Action of effectors amplifies change
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Blood clotting
Oxytocin: Childbirth & Labor
Lactation

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Homeostasis=Dynamic
Constancy

Regulatory mechanisms:
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Intrinsic control is built into organ being regulated

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Extrinsic control comes from outside of organ
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By nervous or endocrine systems
E.g. nervous control of body temperature

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Lack of Homeostasis=
Pathological Condition
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Internal
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Abnormal growth of cells
Autoimmune
Inherited
Failure of cell processes 

External
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Toxic chemicals
Physical trauma
Foreign invaders:
Virus
 Bacteria
 Protozoan
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Body-Fluid Compartments
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Body has intracellular & extracellular compartments 

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Intracellular
 Composed of cytoplasm and organelles
Extracellular
 composed of blood plasma & interstitial fluid Communication between intra and extracellular compartments occurs via osmosis/diffusion
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Table 1-2

Scientific Method

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Scientific MethodObservation and
Experimentation
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1. Form a testable hypothesis about observations

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2. Conduct & analyze experiments to test hypothesis 

3. Draw conclusions about whether or not results support hypothesis
4. Develop a theory
 = general statement explaining natural phenomena that is based on proven hypotheses/reproducible data

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Testing of Hypotheses

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Use of Measurements, Controls &
Statistics

Involves:
 Independent & Dependent variable
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Experimental & control groups

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Quantitative blind measurements

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Analysis of data using statistics

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Peer-reviewed journals
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Scientific Literature
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Peer-reviewed journal articles
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Quality control
Google Scholar (www.scholar.google.com )
Searching the web: http://tilt.lib.utsystem.edu CITE YOUR SOURCE!!!
TCC's Literary Resource Center

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Acknowledge your source