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NOTES: CH 40 – Introduction to
Human Anatomy & Physiology
THE HUMAN BODY
Anatomy
(= structures)
Physiology
(= functions
or processes)
Characteristics of LIFE:
1) Made up of 1 or more
CELLS.
2) Obtain and use energy.
3) Reproduction.
Characteristics of LIFE:
4) Growth /
development - life cycle.
5) Ability to
RESPOND to
environment.
Living Things are ORGANIZED:
molecules  organelles 
CELLS  tissues 
organs  organ systems
 organism!
Structure & Function
● at every level of organization,
we see that “form fits function”
EXAMPLES:
● RIBCAGE: shape fits the
function of support &
protection of the organs in the
thoracic cavity
● SMALL INTESTINE: structure
fits the function of digestion &
absorption of nutrients
• What is a TISSUE?
Tissues are groups of cells with
specialized structural and functional roles.
 Intercellular materials, varying from solid
to liquid, separate cells.
(also known as MATRIX)
• Four Main Kinds of Tissue:
-Epithelial
-Connective
-Muscle
-Nervous
EPITHELIAL TISSUE:
*General Characteristics:
• covers all
free body surfaces
(outer and inner
surfaces of organs)
• major tissue of glands
EPITHELIAL TISSUE:
• anchored to connective tissue by a
BASEMENT MEMBRANE
• lack blood vessels
EPITHELIAL TISSUE:
• nutrients get to the epithelial tissue by
diffusion from the connective tissue below
EPITHELIAL TISSUE:
• readily divide; so injured areas heal quickly
as new cells replace lost or damaged ones
EPITHELIAL TISSUE:
• cells are tightly packed – form effective
protective barriers
EPITHELIAL TISSUE:
• functions include:
protection
secretion
absorption
excretion
EPITHELIAL TISSUE:
• cells are classified according to shape and
number of layers of cells
-simple = single layer of cells
-stratified = two or more layers of cells
-squamous = thin, flattened cells
-cuboidal = cube-shaped cells
-columnar = elongated cells
EPITHELIAL TISSUE:
• free surface cells may have modifications
suited to their function
(i.e. cilia, microvilli, mucus-secreting cells)
• General Characteristics of
CONNECTIVE TISSUE:
 Functions include:
Support
Provide framework
Protect
Fill space
Store fat
Produce blood cells
Connect
Protect against infection
Repair damaged tissue
Connective Tissue:
 Considerable amount of intercellular
material (MATRIX) between cells
*Matrix consists of fibers and ground
substance
Connective Tissue:
 Major Cell Types:
1) Fibroblasts: produce collagenous & elastic
fibers
2) Macrophages: phagocytes (engulf
pathogens)
3) Mast cells: usually near blood vessels;
release heparin and histamine
 Connective Tissue Fibers may be:
1) Collagenous fibers: composed of
collagen; have great tensile strength
2) Elastic Fibers: composed of microfibrils
embedded in elastin; are very elastic
3) Reticular fibers: very fine, collagenous
fibers
• Categories of connective tissue:
 Loose (Areolar)
Connective Tissue:
-forms thin membranes between
organs and binds them
-beneath the skin and between
muscles
 Adipose tissue:
-stores fat
-found beneath the skin, around
kidneys, heart and joints
• Categories of connective tissue:
 Dense connective tissue:
-composed of strong, collagenous fibers
-found in tendons, ligaments, white portion
of eyes, deep layer of skin
• Categories of connective tissue:
 Cartilage:
-provides a supportive framework for various
structures
-cartilage lacks a direct blood supply and is
slow to heal
Fibrocartilage
Elastic cartilage
Hyaline cartilage
• Categories of connective tissue:
 Bone:
-intercellular matrix contains mineral salts and
collagen
-an active tissue that heals rapidly
• Categories of connective tissue:
-transports substances; helps maintain a stable
internal environment
-composed of: red blood cells (RBCs), WBCs,
and platelets in plasma.
-blood develops in red marrow in the hollow
parts of long bones.
MUSCLE TISSUES
 General Characteristics:
• muscle tissues contract, moving structures
that are attached to them
• three types are: SKELETAL, SMOOTH,
and CARDIAC
 Skeletal Muscle Tissue:
• usually attached to
BONES and controlled
by conscious effort
• cells, or muscle fibers,
are long and threadlike
• muscle fibers contract
when stimulated by
nerve impulses, then
immediately relax
 Smooth Muscle Tissue:
• in the walls of hollow internal organs and
blood vessels
• usually it is involuntarily controlled
 Cardiac Muscle Tissue:
• found only in the heart
• cells are joined by intercalated discs and
form branched networks
NERVOUS TISSUES
• in the brain, spinal cord, and peripheral
nerves
 Neurons (Nerve Cells):
• sense changes and
respond by transmitting
nerve impulses to other
neurons or muscles or
glands
• coordinate, regulate, and
integrate body activities
(Nervous Tissue)
 Supporting Cells:
• functions include:
-bind and support
nervous tissue
-phagocytosis
-connect neurons
to blood vessels
Organization
molecules  organelles  CELLS  tissues 
organs  organ systems  organism!
• Organ: structure made of 2 or
more tissues
• Organ system: group of
organs which are concerned
with the performance of one or
more general physiologic goals
together
Anatomical Terms
PROXIMAL
DISTAL
Body Planes:
(FRONTAL)
Body Plan
CAVITIES
Dorsal
Ventral
cranial
spinal
thoracic
abdominal
-surrounds
brain
-surrounds
spine &
spinal cord
(a.k.a.
-heart,
lungs,
trachea,
esophagus
-digestive,
excretory
vertebral cav.)
pelvic
reproductive
BODY CAVITIES:
Overview of Organ Systems:
System
Major
Structures
Function(s)
Skeletal
Bones
structure, support,
movement
Muscular
Muscles
structure, support,
movement
Integumentary
Skin, hair, nails protection,
excretion
Muscular
System
Skeletal
System
Integumentary
System
Overview of Organ Systems:
System
Major
Structures
Function(s)
Circulatory
Heart, blood
vessels
transport
Respiratory
Lungs, air
passages
gas exchange
Immune
Lymph nodes,
B & T cells
fight disease
Respiratory
System
Circulatory System
Immune
System
Overview of Organ Systems:
System
Major
Structures
Function(s)
Digestive
Stomach,
intestines,
esophagus
Kidneys, skin
digestion,
absorption
Excretory /
Urinary
Nervous
removal of waste
Brain, spinal cord, sense,
nerves
coordination,
control
Excretory
System
Digestive
System
Nervous
System
Overview of Organ Systems:
System
Major
Structures
Function(s)
Endocrine
Glands,
hypothalamus
Reproductive
Gonads
control &
regulation of
homeostasis
production of
offspring
Female
Reproductive
System
Endocrine
System
Male
Reproductive
System
Homeostasis
• In general, organ systems participate in
FEEDBACK LOOPS designed to maintain
the status quo of internal environment
(= HOMEOSTASIS)
3 Components of a feedback
system:
• Receptor:
detects a change
in some variable
of the animal’s
internal
environment
(e.g. body temp.)
3 Components of a feedback
system:
• Control center:
processes
information it
receives from
the receptor
(brain,
hypothalamus)
3 Components of a feedback
system:
• Effector: receives
a message from
the control center
and responds
appropriately
(muscles 
shivering,
goosebumps)
NEGATIVE FEEDBACK
• Example
Negative feedback: body temperature
(needs to stay around 37°C)
rise in  brain
 message to  body temp.
temp.
“thermostat” sweat glands
lowers
to produce
sweat
**Negative feedback maintains HOMEOSTASIS!
POSITIVE FEEDBACK
• Example
Positive feedback:
childbirth (body needs
to achieve a heightened
state of exertion…
LABOR!)
pressure 
of baby’s
head
uterine
 more  more
contractions
pressure contractions…..