What is Anatomy & Physiology?
Anatomy – studies the structure of body parts and
their relationship to each other
Physiology – studies the function of the body, in
other words, how it works
Gross Anatomy – the study of large body structures
visible or observable to the naked eye
Examples:
• Stomach
• Liver
• Large Intestine
• Bones
• Eyes
Microscopic anatomy – the study of structures
too small to be seen by the naked eye.
A Look at Physiology
Considers the operation of specific organ systems
Renal physiology – kidney function
neurophysiology – workings of the nervous system
cardiovascular physiology – the operation of the heart and
blood vessesl
Focuses on the functions of the body, often at the cellular or
molecular level
Understanding physiology also required a knowledge of physics,
which explains electrical currents, blood pressure, and the way
muscles use bones for movement
The Principle of Complementarity of
Structure & Function
(Now that’s a mouthful!!!!)
What it all means…
You can’t have one without the other
Function always reflects structure “function follows form”
What a structure can do depends on it’s specific form
For Example:
 Blood flows in one direction through the heart (physiology) because the
heart has valves that prevent backflow (anatomy)
 The lungs can serve as a site for gas exchange (physiology) because the
walls of their air sacs are extremely thin (anatomy)
Levels of Structural Organization (6)
1. Chemical level – atoms combine to form molecules
2. Cellular level – molecules combine to form cells
3. Tissue level – groups of similar cells that have a common function
4. Organ level – at least 2 tissues combined (usually 4) that perform a
specific function
5. Organ system level – consists of multiple organs working closely
together to accomplish a common purpose
6. Organismal level – the result of all structural levels working together
Epithelial
tissue
Smooth muscle
tissue
Connective
tissue
6. Organismal level
Blood
Vessel
Organ Systems of the Body
Integumentary System (skin)
Forms the external body covering
Houses cutaneous nerve receptors
Helps regulate body temperature
Protects deeper tissues from injury
Skeletal System
Protects and supports body organs
Provides attachment for muscles for
movement
Site of blood cell formation
Stores minerals
Muscular System
 Produces Movement
Maintains posture
Produces heat
Nervous System
Fast –acting control system
Responds to external and internal change
Activates muscles and glands
Endocrine system
Secretes regulatory hormones
 Growth
 Reproduction
 Metabolism
Cardiovascular System
Transports materials in our body
via blood pumped by heart




Oxygen
Carbon Dioxide
Nutrients
Waste
Lymphatic System
Returns fluids to blood vessels
Cleans the blood
Involved in immunity
Respiratory System
Keeps blood supplied with oxygen
Removes carbon dioxide
Digestive System
Breaks down food
Allows for nutrient absorption
in the blood
Eliminates indigestible food
Urinary System
Maintains acid-base balance
Eliminates nitrogenous wastes
Regulates
• Water
• Electrolytes
Reproductive
Produces Offspring
Bell work!
(answer in complete sentences)
• What is the principle of complementarity of
structure and function?
• List the 6 levels of structural organization from
most basic to most complex
8 Necessary Life Functions
For Maintenance of Life
Maintain Boundaries - The internal environment
remains separate from the external environment
Cellular level – accomplished by plasma membranes
Organismal level – accomplished by the skin
Movement – includes all activities promoted by the
muscular system (running, swimming, etc…) as well as the
movements we are not even aware of or able to physically
control (heart beating, blood running through your veins,
food traveling the alimentary canal, etc…)
Responsiveness - The ability to sense change in the
environment and respond to it
Digestion – breaking down of ingested foodstuff
Metabolism – All the chemical reactions that occur in the body
• Produces energy
• Makes body structures
Excretion - Removing waste from the body
Reproduction – Produces future generation. Can occur at
the cellular and organismal levels
Cellular level- an original cell divides and produces
two identical daughter cells
Organismal level – Sperm and egg unite to make a
whole new being
Growth – an increase in the size of a body part, cell or
number of cells
6 Survival Needs
The ultimate goal of all
body systems is to maintain
life
Nutrients – chemical substances used for energy and cell building.
Includes:
• Carbohydrates Vitamins
• Proteins
Minerals
• Lipids
Oxygen- needed for metabolic reactions
Water – provides the necessary environments for chemical reactions
• 60-80% of your body is composed of water!
Normal Body Temperature – necessary of chemical reactions
to occur
Atmospheric Pressure – the force that air exerts on the
surface of the body. Required for proper breathing and gas exchange in
the lungs
Homeostasis
The ability to maintain relatively steady internal
conditions even though the outside world changes
continuously
Refers to a state of “balance” or equilibrium, in which
internal conditions vary, but always within narrow limits
Chemical, thermal and neural factors interact to maintain
homeostasis
Homeostatic Control
Mechanisms
Communication within the body is essential for homeostasis
Primarily accomplished by the nervous and endocrine systems
Stimulus – Variable that produces a change in the body
Receptor – sensor that monitors the environment and responds to
changes (stimuli)
Control Center – Determines the set point at which a variable is to
be maintained, analyzes information, determines the
appropriate response
Effector – provides the means to respond to the stimulus
Negative Feedback Mechanisms
• Most homeostatic control mechanisms are negative feedback
mechanisms
• In negative feedback systems, the output shuts off the original
stimulus
• Said to be “negative” because the variable changes in the opposite
direction of the of the initial change, thus returning it to its “ideal”
value
Examples:
• Regulation of blood sugar
• Regulation of body temperature
Positive Feedback Mechanisms
• Positive feedback mechanisms
enhance or exaggerate the original
stimulus so that output is
accelerated or increased
• “positive” because the change that
occurs goes in the same direction
as the initial disturbance, causing
the variable to deviate further and
further away from the original
range.
Example:
• regulation of blood clotting
• Production of oxytocin at birth
Homeostatic Imbalance
Most disease is a result of homeostatic imbalance
As we age, our body’s control systems become less efficient resulting in
our internal environment becoming less stable
Increases our risk for illness and produces the changes we associate with
aging
Anatomical Position
Body is erect with feet
slightly apart, palms facing
forward with thumbs
pointed away from body
Anatomical Position
Directional Terms
Superior (Cephalic) – toward the head or upper part of a structure
Inferior (Caudal) – Away from the head or toward the lower part of
a structure
Anterior (Ventral) – Toward or at the front of the body
Posterior (Dorsal) – Toward or at the back of the body
Medial – toward the midline of the body; in the inner side
Lateral – Away from the midline of the body; on the outer side
Intermediate- between a more medial and a more lateral structure
Directional Terms
Proximal – closer to the origin of the body part or the point of
attachment of a limb to the body trunk
Distal – Farther from the origin of a body party or the point of
attachment of a limb to the body trunk
Superficial (external) – Toward or at the body surface
Deep (internal) – Away from the body surface; more internal
Regional Terms
Axial Part
Makes up the main axis of our body
Included the head, neck, and trunk
Appendicular Part
Consists of the appendages or limbs which are attached to
the body’s axis
Body Planes and Sections
Sagittal plane – a vertical plane that divides the body into riht and
left parts
Midsagittal plane – a sagittal plane that is exactly in the midline
Frontal plane – also called a coronal plane. Divides the body into
anterior (ventral) and posterior (dorsal) parts
Transverse plane – runs horizontally from left to right dividing
the body into superior and inferior parts. Also called a cross section
Body Cavities & Membranes
Dorsal Body Cavity
Protects the nervous system organs
Has 2 subdivisions
•Cranial cavity – within the skull encases the brain
•Vertebral or spinal cavity – runs within the vertebral column,
encloses the spinal cord
Ventral Body Cavity
Houses the ventral organs (viscera)
divided into 2 subdivisions:
•Thoracic
•Abdominopelvic
Body Cavities & Membranes
Thoracic cavity – is divided into the pleural cavities, the
mediastinum, and the pericardial cavity
 Pleural Cavities – contain the lungs
Mediastinum – contains the pericardial cavity and
surrounds the remaining thoracic organs (esophagus, trachea,
etc…)
Pericardial Cavity – contains the heart
Body Cavities & Membranes
Abdominopelvic cavity
 Separated from the thoracic cavity by the diaphram (dome shaped
muscle used in breathing)
Composed of 2 subdivisions:
•Abdominal cavity – contains the stomach, intestines, spleen,
liver and other organs
•Pelvic cavity – located within the pelvis and contains the
bladder, reproductive organs, and the rectum
Ventral Body Cavity Membranes
Serous membrane- very
thin, double layered
membrane lining the ventral
body cavity and the outer
surfaces of the organs
Parietal serosa – lines the
walls of the cavities
Visceral serosa – covers
the organs in the cavity
Serous fluid – separate the
serosae
Abdominopelvic Regions
Abdominoplevic quadrants
The
End