Pathophysiology
The word patho is derived from Greek word Pathos which means suffering and logos
means disclosure or more commonly system of formal study and physio means function
of organism.
Definition of pathophysiology:
It is the systemic study of functional changes in the cell, tissues, and organs altered by the
diseases and or injury.
Cells are divided in to two classes.
Prokaryotes
Eukaryotes
Prokaryotes are unicellular organisms,
found in all environments. Prokaryotes
are the largest group of organisms,
mostly due to the vast array of bacteria
which comprise the bulk of the
prokaryote classification.
Characteristics:
No nuclear membrane (genetic
material dispersed throughout
cytoplasm)
No membrane-bound organelles
Simple internal structure
Most primitive type of cell
(appeared about four billion years
ago)
Examples:
Staphylococcus
Escherichia coli (E. coli)
Streptococcus
Eukaryotes are generally more
advanced than prokaryotes. There
are many unicellular organisms
which are eukaryotic, but all cells
in multicellular organisms are
eukaryotic.
Characteristics:
Nuclear membrane
surrounding genetic
material
Numerous membrane-
bound organelles
Complex internal
structure
Appeared approximately
one billion years ago
Examples:
Paramecium
Dinoflagellates
sapiens
It is hypothesized that a primitive
bacterium once surrounded its
food after releasing its digestive
enzymes. The membrane folded
inward and pinched off, creating
the first digestive membrane-
bound organelle.
And now kids, it's storytime!
Once upon a time (about one
billion years ago), the first
eukaryotic cell came to be. There
was a group of primitive bacteria
going about their business when
along came a big hungry
phagocyte, who ate one of the
bacterium.
Mr. Phagocyte: Yum.
Bacterium: Excuse me.
Mr. Phagocyte: What?
Bacterium: You know, why don't
we join forces and I can help you
and you can help me and we can
become a 'eukaryotic' cell?
Whaddaya say?
Mr. Phagocyte: OK.
The little engulfed bacterium
evolved and became the
mitochondria in present-day cells.
Obviously, they all lived happily
ever after.