Unit 1

noisymaniacalΒιοτεχνολογία

20 Φεβ 2013 (πριν από 4 χρόνια και 7 μήνες)

122 εμφανίσεις

Unit 1

The Science Of Microbiology

Donna Howell

Medical Microbiology

Gaffney High School

What is Microbiology?


Microbiology is
defined as the study
of the structure,
function, uses, etc. of
microscopic
organisms.


It is a specialized
branch of Biology.

Why Microbes Matter


Here’s how they affect our lives:


Cause disease


Decompose dead organisms


Help maintain balance of nature


Capture energy from Sun for re
-
use


Can be used to control other pests


Used in genetic engineering


Used to make food products


Used to produce medicines


Can be used to clean up oil spills


Microbes
RULE!

The First Observations


In 1665, Robert Hooke was
the first to notice that life’s
smallest living units were
made up of cells, which was
the beginning of the cell
theory.


In the late 1600’s, Antoni
van Leeuwenhoek invented
the first true microscope. He
was the first to describe
living microbes.

Spontaneous Generation


Up until the
1800’s, scientists
believed that life
could arise
spontaneously
from nonliving
matter.

Spontaneous Generation


In 1668, Francisco
Redi demonstrated
that maggots did
NOT arise
spontaneously
from meat. This
was the beginning
of the proof that
spontaneous
generation did not
exist.

Spontaneous Generation


In 1858, Rudolf
Virchow challenged
spontaneous
generation with the
concept of biogenesis,
which says that living
cells can ONLY arise
from other living
cells.

Spontaneous Generation


In 1861, Louis Pasteur
settled the issue. He
proved that microbes
can be destroyed by
heat.


This was the beginning
of aseptic technique,
which is the use of
techniques that prevent
contamination by
unwanted microbes in
laboratories and
medical facilities.


He is also credited with
the development of the
“germ theory of
disease”, which says
that microbes cause
disease.

Golden Age of Microbiology


Beginning in 1857 with
Pasteur’s discovery of germ
theory of disease, and for
the next 60 years, many
branches of microbiology
were established and many
new microorganisms were
discovered.


This was called “The
Golden Age of
Microbiology” due to the
many discoveries!

The Golden Age of Microbiology


During the “Golden Age”,
many other discoveries were
made:


Electron microscope invented


could see viruses for the first
time!


Antibiotics were discovered


More research money available
after war was over


Genes beginning to be studied


The Golden Age of Microbiology


There were other
accomplishments too:


In 1796, Edward Jenner was
the first to “vaccinate” people
against smallpox.


In late 1800’s, Pasteur
discovered fermentation and
pasteurization


In the 1860’s, Joseph Lister
began using aseptic technique
to medical procedures


In 1876, Robert Koch proved
that bacteria caused disease
(Koch’s Postulates)



Birth of Modern Chemotherapy


Now that scientists knew
microbes caused disease, they
tried to find ways to cure
disease.


Treatment of disease by using
chemical substances is called
“chemotherapy”.


In 1910, Paul Ehrlich came up
with the first synthetic drug (not
an antibiotic) used to treat
syphilis.


In 1928, Alexander Fleming
discovered the first antibiotic,
Penicillin

Modern Microbiology


There are now many branches of
microbiology due to specialization:


Bacteriology


study of bacteria


Mycology



study of fungi


Parasitology



study of protozoa
and parasitic worms


Virology



study of viruses


Immunology


study of the immune
system and how it responds to
microorganisms


Genomics



study of genes


Biotechnology



use of microbes in
practical ways


Introducing….Archaea!


The first group of microbes
we will study is the Archaea.
These are the “ancient”
bacteria


they have cell
walls different than normal
bacteria, and live in extreme
environments:


Thermophiles



found in
HOT temperatures


Psychrophiles



found in
COLD temperatures


Halophiles



found in
SALTY habitats


Acidophiles



found in
ACIDIC habitats

Hot Springs

Deep Sea Hydrothermal Vent

Introducing….Bacteria!


Found everywhere


literally!


Can be autotrophic
or heterotrophic.


Can live with or
without oxygen.


Can be beneficial or
harmful.


Most numerous
organisms on
Earth.


Introducing….Viruses!


Made of a core of
nucleic acid and a
protein coat.


Cannot survive on own


need a host cell.


Can infect ANY type of
cell, not just human.


Smallest of all microbes.


Two subgroups:


Viroids


only contain
nucleic acid


Prions


only contain
protein coat

Introducing….Protozoa!


A type of Protist that is
medically significant


very diverse group.


Includes 4 subgroups:


Ciliates



move with
cilia, or hairs


Flagellates



have
flagella for movement


Sarcodines



move
with pseudopods, or
false feet


Apicomplexans



do
not move; need a host
animal

Giardia

Trypanosoma

Plasmodium

Introducing….Algae!


Plant
-
like microorganisms, can
undergo photosynthesis.


Produce 75% or more of
planet’s oxygen


Important to the food chain


Types:


Green algae


most like plants;
found in water


Diatoms


hard shell; found in
ocean


Dinoflagellates


found in ocean;
can glow. Cause of red tide.


Cyanobacteria

Diatoms

Dinoflagellates

Introducing….Fungi!


Can be single
-
celled to
multi
-
cellular


Decomposers of organic
matter


Have cell walls of chitin


Heterotrophic; absorb
food


Cannot undergo
photosynthesis


Examples: mushrooms,
slime molds, water
molds

Yeast Cells

Introducing….Helminths!


Also known as
parasitic worms.


Multicellular,
eukaryotic animals


Must have host(s) to
reproduce.


Examples:
hookworm,
pinworms, etc.

Hookworm

Ascaris

Introducing….Parasitic Insects!


Insects that are
human parasites
are also included in
the field of
microbiology.


Examples are
scabies, crabs, head
lice, and some
others.


The End!