Chapter 1 – Introduction to anatomy and
physiology
A new language
What knowledge should I bring to A&P course?
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Basic math – mean, fractions, percents, ratios,
proportions, metric system, tables, graphs and charts
Basic chemistry – matter, elements, atomic structure,
chemical interactions, bonds, chemical reactions,
molecules/macromolecules,
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Animal cell biology – membrane, organelles, cell cycle
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Microscopy

Cell transport mechanisms – osmosis, diffusion and
active transport
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Enzymes
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Scientific method and how to write lab report
Keep in mind.........
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Anatomy explains physiology

Form and function are interrelated
Overview of Anatomy and Physiology

Anatomy – the study of the structure of body parts and their
relationships to one another
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Gross or macroscopic – large visible body structures (heart,
lungs, kidney etc.)
Different ways to approach gross anatomy:
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Regional – study of all the structure in a particular region of the
body (leg, abdomen etc.)
Systemic – study a particular system at a time.
Microscopic – deals with structures that are too small to be seen
with the naked eye
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Cytology – relates to the cells
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Histology – study of the tissues
Physiology – the study of the function of the body
Specialized Branches of Anatomy
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Pathological anatomy – study of structural
changes caused by disease
Radiographic anatomy – study of internal
structures visualized by specialized scanning
procedures such as X-ray, MRI, and CT scans
Molecular biology – study
structures at a subcellular level
of
anatomical
Anatomical Position

Body erect

feet slightly apart

palms facing forward

thumbs point away from
body
The new language – anatomical position

The anatomical position is extremely important in
studying anatomy since it is universal.

This allows professionals to easily communicate with
each other, even if they are from different countries or
backgrounds

Regardless of the patient body position – you
ALWAYS refer to anatomical position
Other concepts you need to know if you want to speak
the language
(you’ll do most of it in the lab)

Body planes

Dorsal and ventral cavities
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Abdominopelvic quadrants and 9 regions
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Organ systems
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Membranes
Systems covered in A&P I
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Integumentary – cover, protection, sweat, receptors
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Nervous system – control
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Skeletal system – support, protection, calcium,
blood cells, movement
Muscles - movement
Systems covered in A&P II
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Endocrine system – hormonal regulation
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Cardiovascular system
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Lymphatic system/immunity
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Respiratory system
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Digestive system
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Urinary system
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Reproductive system
Necessary Life Functions
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Maintaining boundaries – the internal environment remains
distinct from the external environment
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Cellular level – accomplished by plasma membranes
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Organismal level – accomplished by the skin
Movement – locomotion, propulsion (peristalsis), and
contractility
Responsiveness – ability to sense changes in the
environment and respond to them
Digestion – breakdown of ingested foods
Metabolism – all the chemical reactions that occur in the
body (we will study in details in A&P II)
Necessary Life Functions

Excretion – removal of wastes from the body
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Reproduction – cellular and organismal levels
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Cellular – an original cell divides and produces two
identical daughter cells
Organismal – sperm and egg unite to make a whole
new person
Growth – increase in size of a body part or of the
organism
Survival Needs
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Nutrients – needed for energy and cell building
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Oxygen – necessary for metabolic reactions
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Water – provides the necessary environment for
chemical reactions (60-8% of body weight)
Normal body temperature – necessary for chemical
reactions to occur at life-sustaining rates (why is it
important to maintain core body temperature?)
Atmospheric pressure – required for proper
breathing and gas exchange in the lungs
Homeostasis
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Homeo – unchanging + stasis – standing
The ability to maintain a relatively stable internal
environment in an ever-changing outside world
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Homeostatic regulation is the adjustment of physiological
systems to preserve homeostasis
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The internal environment of the body is in a dynamic state
of equilibrium – it is not a precise value
It happens in an environment that is inconsistent,
unpredictable and at times – dangerous
Failure to maintain homeostasis can lead to illness or even
death
Homeostatic control

Homeostasis is a continuous process that uses physiological
control system to monitor key functions
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Some aspects of control systems:
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Nervous system – coordinates and integrates conditions that
are compatible with normal functions: blood volume, blood
osmolarity, blood pressure, body temperature etc.
Tonic control – maintaining “moderate activity” – example –
blood vessel diameter. Tonic control is not stopping or starting
activity (similar to turning radio volume louder or softer)
Antagonistic control – for systems that are not under tonic
control either by hormones or the nervous system (insulin and
glucagon, sympathetic and parasympathetic)
Local and long-distance control pathways
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Local control – in the cell or tissue – autocrine or
paracrine mechanisms (CO2 levels in the tissue
influence diameter of local capillaries)
Long distance control involves the nervous and
endocrine systems.
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The long distance control involves 3 components –
sensor, integration center and effector
Homeostatic Control Mechanisms components
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Variables produce a change in the body
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The three interdependent components of control
mechanisms:
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Receptor – monitors the environments and
responds to changes (stimuli)
Control center – determines the set point at which
the variable is maintained
Effector – provides the means to respond to
stimuli
Define Negative Feedback
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In negative feedback systems, the output shuts off
the original stimulus
Positive Feedback

In positive feedback
systems, the output
enhances or exaggerates
the original stimulus
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Example: Regulation of
blood clotting

Positive feedback is also
known as a “vicious
cycle” – if not stopped
can lead to death
Figure 1.6
Some environments in our body – fluid compartments

Fluids in the body are compose of water and solutes

There are 2 distinct fluid compartments
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Intracellular fluid (ICF)
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The cytosol of cells
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Makes up about two-thirds of the total body water
Extracellular fluid (ECF)

Major components include the interstitial fluid,
plasma and lymph

Minor components include all other extracellular
fluids (water in dense CT, bone, fluid between
visceral and parietal membranes etc.)
Important components and characteristics of ECF*
Normal range
Approximate
short-term
nonlethal limit
Oxygen
35-40
10-1000
mmHg
Carbon dioxide
35-45
5-80
mmHg
Sodium ions
138-146
115-175
mmol/L
Potassium ions
3.8-5.0
1.5-9.0
mmol/L
Calcium ions
1.0-1.4
0.5-2.0
mmol/L
Chloride ions
103-112
70-130
mmol/L
Bicarbonate ions
24-32
8-45
mmol/L
Glucose
75-95
20-1500
Mg/dl
98-98.8 (37.0)
65-110 (18.343.3)
0F (0C)
7.3-7.5
6.9-8.0
Body temperature
Acid-base
Medical Physiology – Guyton and Hall, 11th ed.
units
pH