Introduction to Human
Anatomy and Physiology
Anatomy and Physiology
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Anatomy -- deals with the structure of the
body and its parts
Physiology -- studies the functions of these
parts or asks the question, “how do they
work?”
Structure and function closely related
Which field is most likely to have new
discoveries? Why?
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To send a nerve impulse, sodium and
potassium ions must switch places in the cell.
The human tailbone is a fusion of multiple
vertebrae.
When the bicep muscle contracts, it pulls on
tendons and ligaments which move the lower
arm toward the upper arm.
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Levels of Organization:
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Characteristics of the human
organism
1.
2.
3.
4.
5.
6.
7.
8.
9.
Movement (either gross or movement of internal organ)
Response to stimuli
Growth
Reproduction
Respiration (take in oxygen, out with carbon dioxide)
Digestion
Absorption (nutrients taken into bloodstream)
Circulation (movement of substances in bodily fluids)
Assimilation (changing absorbed substances into chemically
different forms)
10. Excretion
Metabolism: all chemical reactions at work to maintain/allow for these
.
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Life depends on the availability of:
a. Water
b. Food
c. Oxygen
d. Heat (a by-product of metabolism; affects reaction rates)
e. Pressure (force required for movement of air and fluids)
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Dynamic process of self-regulating controls
which create a stable internal environment
External conditions are always changing
To survive, internal conditions must remain
relatively stable…How???
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Maintaining a stable
internal
environment
Organ systems
function to maintain
homeostasis
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Examples?
1.
Body has a set point (normal, balanced)
2.
Receptors in the body detect deviations
away from set point
3.
Brain interprets information
4.
Triggers a set of events (using effectors) to
bring the situation back to normal
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NEGATIVE FEEDBACK – Correction occurs
opposite direction of stimulus
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Examples:
 Body temp rises; cooling mechanisms activated
 Body temp drops; heating mechanisms activated
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Other examples?
Blood sugar levels, blood oxygen levels
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POSITIVE FEEDBACK - Stimulus amplifies
response in the same direction
Why?
Examples:
 Chemicals present in a blood clot lead to
more clotting
 A baby drinking mother’s milk causes more
milk production
 Pressure in the uterus during childbirth
leads to stronger contractions
Positive Feedback responses are typically
short-term… why?
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VITAL SIGNS
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A measure of homeostasis
Indicate that someone is alive
What is measured in a test of vital signs?
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Monitored to determine level of health:
Vital Sign
What is it?
Normal
Body Temp
97o-100oF
Blood Pressure
100/60 - 140/90
Heart Rate
60-100 beats/min
Resp Rate
12-20 breaths/min
Pupils
Dilate and contract
Blood O2 level
>90%
Reflexes
Responsive
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Lots of vocabulary to describe the body
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Why?
 Allows doctors/health professionals to communicate as
clearly as possible
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Which would you rather hear as a surgeon?
 “It hurts in the left upper side of my chest.”
 “I’m having pain in the left lateral pleural cavity,
superior to the heart.”
Organization of Body - Body Cavities
AXIAL (head, neck, trunk) vs. APPENDICULAR (upper and lower limbs)
Ventral Cavity: Front (anterior)
-thoracic cavity
-diaphragm
-abdominopelvic cavity
Dorsal Cavity: Back (posterior)
-cranial cavity
-vertebral (spinal) cavity
PARIETAL –
lines body cavity
VISCERAL –
covers organ
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Thoracic Cavity
contains
pleural (lung)
pericardial (heart)
cavities
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Always refer to body
in ANATOMICAL
POSITION
Face forward
 Palms forward
 Note: Right and left
refer to the patient
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Anatomical Terminology
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Relative Positions:
Terms used to describe the location of a body
part relative to another part.
Terms include:
superior (closer to the head), inferior
anterior (towards the front), posterior
medial (closer to midline), lateral
proximal (closer to trunk), distal
superficial (towards the surface), deep
ipsilateral (on same side), contralateral
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Anatomical Terminology - Body Sections
1. A sagittal (median) section divides the
body into right and left portions.
2. A transverse (cross) section divides the
body into superior and inferior portions.
3. A coronal (frontal) section divides the
body into anterior and posterior sections.
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The lesion is
located in the right
thoracic cavity just
lateral to the midsagittal plane.