Organization of the Body PPT Revised

Unit 2
Organization of the Body
Hierarchy of Human Structure
Guided Reading:
1. List the levels of organization, starting
with molecules.
2. What are stem cells?
Hierarchy: a series of ordered
groupings within a system
Alpha male &
Pups & adults
Outcasts / Dispersers
Levels of Organization
Stem Cells
 Undifferentiated
have the potential to develop into many different
cell types during early life & growth
Can be induced to become specialized cells
 brain
cells, red blood cells, skin cells, etc.
 Embryonic
stem cells: derived from fertilized eggs
 Induced pluripotent stem cells: adult specialized
cells that can be “reprogrammed” to become a
different kind of cell
 Blastocyst (early stage of development)
stem cells differentiate into specialized cells
 Adults:
stem cells still exist (in organs & bone
marrow) to replace old/damaged cells
The Human Physiological
Guided Reading:
1. If humans live on land, why does the
author say that the human physiological
environment is “aqueous”?
2. What does it mean when people say
that something acts as a “solvent”?
The Human Physiological
 All
the internal conditions that allow cells to
perform their functions effectively & efficiently.
This positively impacts body organization
 Involves internal & external cellular conditions.
 Both rely on water.
Needs specific conditions to maintain homeostasis:
 pH,
ions, chemical reactions, transport of molecules
between internal & external environments
 Allows
us to maintain homeostasis…
More on homeostasis
 Homeostasis
≠ balance.
 Allows us to adapt to changing
environments. Maintained by negative
feedback loops
 Maintain constant conditions inside the
body when the external environment
 “Set
 Often
utilizes chemical messengers (e.g.
Negative Feedback Systems
Negative Feedback:
Maintaining Homeostasis
 “System”
has a set point (ideal level) and
“sensors” that detect changes…
 If it drops below set point, something is
 If it exceeds that level, production stops…
 Examples:
Body Temperature Example
Negative Feedback Loop
Generic Example:
X releases hormone X…
 This
stimulates target cells to
release hormone Y.
 Eventually, an excess of hormone
Y exists
 Gland X "senses" this… and inhibits
its release of hormone X.
Positive Feedback
 “Feedback
in which the system responds
so as to increase the magnitude of any
particular perturbation”
 Results
in amplification of the original
signal instead of stabilization.
 Any system where there is a net positive
feedback will result in a runaway
 Requires a feedback loop to operate.
 Examples: Fruit ripening, childbirth,
The Human Physiological
 The
human physiological environment is aqueous.
 Water is contained in the cells, the blood, body
cavities, organ systems, and tissue.
Not just sloshing around under the skin!!
 Water’s
atomic structure provides it with all the
properties that make it useful for the body.
The universal solvent. . . .
 Water
is polar  can dissolve most materials
needed for human survival
 Solvent = dissolves other chemicals & forms a
 Solute = a particle that is dissolved in a solvent
 Water is a good bio solvent b/c it is polar (charged)
 Most chemical reactions require an aqueous
 Water
is a natural solvent for ions, needed for
cellular functions
 Adhesion & cohesion  won’t evaporate quickly
(so we won’t become easily dehydrated)
 High specific heat  water absorbs much heat
energy when it evaporates
Living in a balance
 Dehydration:
Indicators: extreme thirst, stop sweating, nausea &
 Water
tissues deprived of water
Body takes in more water than it loses at a given
period of time.
Upsets natural balance of ions, minerals
A Fraternity Hazing Gone Wrong : NPR
Guided Reading:
1. What are the four types of tissue found in
2. What are the major
characteristics/functions of the four
types of tissue? (Recommend you make
a chart)
Stem cells again!!!!
 Retain
ability to undergo cell division
 Assist further body development and
healing later in life
 Stem cells from bone can produce a
variety of human tissues
 Brain stem cells can develop into many
types of cells
Embryological germ layers
 Ectoderm
 skin and brain
 Mesoderm  Bone and muscle
 Endoderm  Digestive organs
 Lay
down the 4 human tissue types into
the hierarchy that eventually forms a
Create a Concept Map (aka
Mind Map) for One Type of
 How
to create a concept map
 Constructing a concept map
 Example
 For each cell type…..
Names of cells & structures
Four Types of Tissues
Connective: forms the
supportive framework
of the organs & body
Epithelial: covers
internal & external
body surfaces; forms
layers of cells that line
body cavities
Muscle: provides body
w/ movement &
Nervous: conducts &
coordinates body info;
highly specialized cells
Tissue Type
Types of
Characteristics of these cells
Cube-shaped; produce secretions
Tall, column-shaped; secretions, uptake
Simple: Single-layer
Stratified: Multi-layered; subject to wear and
Pseudostratified: False-stratification
Protein: Collagen
Protein: Elastin
Protein: Reticulum
Made of gel, liquid, protein, salts
Most abundant; attachment, stabilization,
structure, support
Strength, storage, flexibility
Spindle-shaped; no visible fibers; weak
contractions; line organs
Heart; visible striations; intercalated disks
Large cells; distinct striations; (in)voluntary
Motor, Sensory, Interneuron
Assist Neuron functions (astrocytes,
oligodendites, ependymal cells)
Organs, and Systems
Guided Reading
1. What is the relationship between tissues
and organs/systems?
2. What are the various organ systems
found in humans?
Organs and Systems
Cardiovascular  regulates blood flow
Digestive  regulates nutrition
Integumentary  provides protection
Lymphatic  regulates body fluids, helps fight disease
Muscular  provides structure and movement
Skeletal  provides support and movement
Endocrine  regulates body function and
Reproductive  regulates sexual function
Respiratory  regulates atmospheric gasses and
certain body wastes
Urinary  regulates production, storage, and removal
of urine
Wellness and Illness over the
Life Span
Guided Reading:
1. What does this statement mean? “Cell
pathology causes hierarchy dysfunctions of
the body”?
2. What is the purpose of a biopsy?
3. Make a chart describing the major types of
cell pathology.
4. What is “molecular decay”?
5. What does “telomere shortening” cause for
a cell?
Cell Pathology
 The
basis of understanding dysfunction of the
body’s hierarchy
 Dysfunction: Abnormal, impaired, or incomplete
functioning of an organism, organ system, organ,
tissue or cell. All gross diseases.
 Cell pathology: examining cells microscopically
Biopsy: Removal of diseased cells for study
Types of Cell Pathology
 Dys: bad, abnormal
 A: not
 Hyper: over, above, exceedingly, in excess
 Meta: changed; altered
 Trophy: make to thrive
 Plasia: formation
 Stasis: place
Cell Pathology Terms
 Atrophy:
or organ.
Wasting or decrease in size of a cell, tissue
Caused by malnutrition / blood flow problems
Lack of muscle use / nerve damage  muscle
 Dystrophy:
“ill growth.” progressive changes in a
tissue that is almost always due to long-term
malnutrition, decreased blood flow.
Muscular dystrophy: general weakening of muscles
 Hypertrophy:
Enlargement of a tissue or organ due
to an increase in cell size, NOT CELL NUMBER.
Cell Pathology Terms
Dysplasia: disorderly growth pattern in a tissue or organ.
Hyperplasia: abnormal multiplication in the number of
normal cells in a tissue
Not cancerous
Has significant impact on body structure
Increases the risks of certain cancers
Distorts the function of the tissue/organ
Metaplasia: A change in cell and tissue function from
normal to abnormal.
Can be reversible
Can produce inappropriate functioning of the tissue or
Cause: DNA damage, exposure to certain chemicals
Can lead to cancer or breakdown in cell communication /
tissue organization
Cell Pathology Terms
 Metastasis:
Diseased cells break away from
the original location and establish themselves
in new areas of the body
Can carry out functions in new location
Reserved from cancerous or highly abnormal
Cell Pathology: Amyloid deposition
 Amyloid:
protein-like material
 Disagreement: do they cause disease or are they
the result of disease?
Intended to help but cause harm when build up in
 Indicators
of cell damagecell senses & corrects
 Cell death is the result usually
Cell Pathology: Fatty Change
 Accumulation
of lipids in the cell in
response to cellular injury.
 Excessive alcohol intakeincreased fat in
liver cells, disrupting cell function & thus
tissue function
Cell Pathology: Necrosis
 Localized
tissue death
 Blood flow decrease (bed sores!) burns,
chemical damage, infections, injury
 Results in diminished functioning of the
tissue, organ & organ system.
Cellular Aging: Non-mitotic cells
 Occurs
because of accumulated molecular
Especially in cells that cannot undergo mitosis: fat
cells, skeletal muscle, nervous tissue.
They can’t fix the damage
Fail at tasksaffect tissues, organs, etc.
Caused by environmental factors, stress
Cells can die early or undergo programmed death
protect the nearby cells

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