Download The Human Body in Health and Disease

The Human
Body in Health
and Disease
Chapter 2
STRUCTURES OF
THE BODY
•Body
anatomy: made up of increasing
larger and more complex structural units
•Cells  tissues  organs  the body
systems
Body Systems
 Skeletal
 Urinary
 Muscular
 Nervous
 Cardiovascular  Special
 Lymphatic
 Immune
 Respiratory
 Digestive
Senses
 Integumentary
 Endocrine
 Reproductive
CELLS
•The
basic structural and functional units of
the body
•They
specialize and group together to form
tissues and organs
•Cytology – the study of the anatomy,
physiology, pathology and chemistry of the
cell
The Structure of Cells
Cell Membrane – the tissue that
surrounds and protects the contents of the
cell by separating them from its external
environment
 Cytoplasm – material within the cell
membrane that is not part of the nucleus
 Nucleus – surrounded by a nuclear
membrane; a structure within the cell that
has two important fxns:

Controls the activities of the cell
 Helps the cell divide

Stem Cells

Unspecialized cells that are able to renew
themselves for long pds of x by cell division


In contrast to other cell types that have a
specialized role and die after a determined lifespan
Under certain conditions stem cells can be
transformed into cells with special fxns such as
the cells of the heart m that make the
heartbeat possible or the specialized cells of the
pancreas that are capable of producing insulin

Adult Stem Cells
 Somatic
Stem Cells; undifferentiated (no
special fxn) cells found among differentiated
(have a specialized fxn) cells in a tissue or
organ
 Maintain
and repair the tissue in which they are
found
 Have the potential to be transplanted from one
individual to another
Found in donor’s bone marrow
 Has to be an excellent match between donor and
recipient


Graft versus host disease

Embryonic Stem Cells

Undifferentiated! Unlike an specific adult cell;
have the ability to form ANY adult cell!!!
 Grow
rapidly and indefinitely in a lab and could
potentially provide a source for adult m, liver, bone, or
blood cells
 They are more primitive than adult stem cells,
therefore a perfect match is not required
 Found in cord blood in the umbilical cord and placenta
 Can also be obtained from surplus embryos produced
by in vitro (test tube) fertilization
•GENETICS
•Gene
– a fundamental physical and
functional unit of heredity
•Control
hereditary disorders and all
physical traits such as hair, skin and eye
color
•Genetics
– the study of how genes
transfer from parent to child(ren) and
the role of genes in health and
disease
•Dominant and
Recessive Genes
•
Each newly formed individual receives two genes of
each genetic trait: one from the father, one from the
mother
•
•
•
Dominant Gene – the offspring will inherit that genetic
condition
A recessive gene inherited from both parents means the
offspring will have that condition
A recessive gene from only one parent, and a normal gene
from the other parent, the offspring will not have the
condition
• Dominant
Gene: ex –
freckles are a dominant trait
• Recessive sickle cell +
recessive sickle cell = child
WILL HAVE sickle cell
• Recessive sickle cell +
normal cell = child WILL NOT
HAVE sickle cell, but will
carry the trait
• The
Human Genome
• Genome
– the complete set of
genetic information of an
individual
• The Human Genome Project was
formed to study this genetic
code in all people and
throughout the world
• Found
that over 99% of the genetic
code is the same among human
beings throughout the world
•Chromosomes
• Chromosomes
– the genetic
structures located within the
nucleus of each cell
• Made up of DNA molecules
that contain the body’s
genes – helps keel a lg
amount of info neat,
organized, and compact
• Somatic
Cell – any cell in the body
other than gametes (sex cells) – 46
chromosomes arranged into 23 pairs;
22 identical pairs and one other…
either XX or XY (fem/male)
• Sex Cell – gamete; only type of cell
that does not contain 46
chromosomes – each ovum (egg) or
sperm has a single set of 23
chromosomes… in a female, one will
be an X and in a male one will be an
X or Y; the X or Y from the father
determines the sex of the child
•DNA
• DNA
– deoxyribonucleic acid; the basic
structure of the DNA molecule
Packaged on a chromosome as 2 spiraling
strands that twist together to form a double
helix; looks like a spiral staircase and consists of 2
strands twisted together
• Found in the nucleus of every cell except RBCs
• DNA is different for every individual and no two
patterns are the same… EXCEPT??? Identical
TWINS! (formed from 1 fertilized egg that divides)
identical genetic make up, but individual finger
prints and other characteristics
•
•Genetic Mutation
• Genetic
mutation – a change in the
sequence of a DNA molecule (radiation
or environmental pollution may be a
cause)
• Somatic
cell mutation – a change within
the cells of the body; affect the
individual but cannot be transmitted to
the next generation
• Gametic cell mutation – a change within
the genes in a gamete that can be
transmitted by parent to his/her child
• Genetic Engineering – manipulating or
splicing of genes for scientific or medical
purposes
•Genetic Disorders
• Genetic
Disorder – hereditary disorder; a
pathological condition caused by an
absent or defective gene
Cystic Fibrosis (CF) – a genetic disorder that is
present at birth and affects both the
respiratory and digestive systems
• Down Symdrome (DS) – a genetic variation
that is associated with characteristic facial
appearance, leaning disabilities, and
physical abnormalities
• Hemophilia – a group of hereditary disorders
in which a blood-clotting factor is missing
•
•
Huntington’s Disease (HD) – a genetic disorder
that is passed from parent to child
• Each
child has a 50-50 chance of inheriting the
defective gene (causes nerve degeneration =
uncontrolled movements and the loss of some mental
abilities)
Muscular Dystrophy – the term used to describe a
group of genetic diseases that are characterized
by progressive weakness and degeneration of the
skeletal mm that control movement
• Phenylketonuria – PKU; a genetic disorder in
which the essential digestive enzyme
phenylalanine hydroxylase is missing
• Tay-Sachs Disease – a fatal genetic disorder in
which harmful quantities of a fatty substance
build up in tissues and nerve cells in the brain
•
TISSUES
•Tissue
– a group or layer of similarly
specialized cells that join together to perform
certain specific functions
•4
Types: epithelial, connective, muscle, and nerve
•Histology – the study of the structure,
composition, and function of tissues
•Histologist – a specialist in the study of the
organization of tissues at all levels
Epithelial Tissues

Epithelial Tissues – form a protective
covering for all of the internal and external
surfaces of the body
Epithelium – the specialized epithelial tissue
that forms the epidermis of the skin and the
surface layer of mucous membranes
 Endothelium – the specialized epithelial tissue
that lines the blood and lymph vessels, body
cavities, glands and organs

Connective Tissues

Connective Tissues – support and connect
organs and other body tissues. 4 Kinds:




Dense Connective Tissues – bone and cartilage,
form joints and the framework of the body
Adipose Tissue – fat; provides protection,
padding, insulation, and support
Loose Connective Tissue – surrounds various
organs and supports both nerve cells and blood
vessels
Liquid Connective Tissues – blood and lymph
Muscle Tissue
Muscle
Tissue –
contains cells with
the specialized
ability to contract
and relax
Nerve Tissue
Nerve
Tissue – contains
cells with the specialized
ability to react to stimuli
and to conduct electrical
impulses
Pathology of Tissue
Formation


Frequently due to unknown causes, can
occur before birth as the tissues are
forming, or appear later in life
Incomplete Tissue Formation
Aplsia – the defective development, or the
congenital absence of an organ or tissue (awithout, -plasia formation)
 Hypoplasia – the incomplete development of
an organ or tissue usually die to a deficiency
in the number of cells (hypo- low)

 Abnormal
Tissue Formation
 Anaplasia
– a change in the structure of cells
and in their orientation to each other (anaexcessive)… characteristic of cancer
 Dysplasia – an abnormal development of growth
or cells, tissues, or organs (dys- bad)
 Hyperplasia – the enlargement of an organ or
tissue because of an abnormal increase in the
number of cells in the tissues
 Hypertrophy – a general increase in the bulk of
a body part or organ that is due to an increase in
the size but not in the number of cells in the
tissues (-trophy development)
GLANDS
 Gland
– a group if specialized
epithelial cells that are capable of
producing secretions
 Exocrine
Glands – secrete chemical
substances into ducts that lead either
to other organs or out of the body
 Endocrine Glands – shave no ducts;
instead, release hormones into the
bloodstream
Pathology and
Procedures of the Glands







Adenitis – inflammation of a gland (aden/ogland)
Adenocarcinoma – a malignant tumor that
originates in glandular tissue
Adenoma – a benign tumor that arises in, or
resembles, glandular tissue
Adenomalacia – the abnormal softening of a
gland
Adenosis – any disease condition of a gland
Adenosclerosis – the abnormal hardening of a
gland
Adenectomy – the surgical removal of a gland
BODY SYSTEMS
AND RELATED
ORGANS
A
body organ is a
somewhat
independent part of
the body that
performs a specific
function
PATHOLOGY
 Pathology
– the study of the nature
and cause of disease that involves
changes in structure and function
 Pathologist
– specializes in the
laboratory analysis of tissue samples to
confirm or establish a diagnosis
 Can
be removed in biopsies, during
operations, or in postmortem exams
 Etiology
disease
– the study of the cause of
Disease Transmission
A pathogen is a disease-producing
microorganism
 Transmission is the spread of disease
 Contamination means that a pathology is
possibly present


Communicable Disease – contagious
disease; any condition that is transmitted
from one person to another either by direct
or indirect contact with a contaminated
object
Indirect Contact Transmission – refers to
situations in which a susceptible person is
infected by contact with a contaminated surface
 Bloodborne Transmission – the spread of
disease through contact with blood or other
body fluids that are contaminated with blood
(HIV, STDs, HepB)
 Airborne Transmission – occurs through
contact with contaminated respiratory droplets
spread by a cough or sneeze

 Food-borne
and Waterborne
Transmission – fecal-oral transmission;
caused by eating or drinking contaminated
food or water that has not been properly
treated to remove contamination or kill
pathogens that are present
 Vector-borne Transmission – is the
spread of a certain disease due to the bite
of a vector
 Flies,
mites, fleas, ticks, rats and dogs
Outbreaks of Diseases

Epidemilogist – a specialist in the study
of outbreaks of disease within a population
 Endemic
– the ongoing presence of a
disease within a population, group or area
 Epidemic – is a sudden and wide-spread
outbreak of disease within a specific
population, group or area
 Pandemic – an outbreak of a disease
ocurring over a large geographic area,
possibly world wide
Types of Disease
 Functional
Disorder – produces
symptoms for which no physiological
or anatomical cause can be identified
(panic attack)
 Iatrogenic Disease – an unfavorable
response due to prescribed medical tx
(burns from radiation tx)
 Idiopathic Disorder – illness without
known cause
 Nosocomial
Infection – a
disease acquired in the hospital or
clinic setting (MRSA)
 Organic Disorder – produces
symptoms caused by detectable
physical changes in the body
(chickenpox)
Anatomic Reference Systems