Transcript Ch 11 & 12 Notes

Microbes Notes
Microscopic Organisms and Your
Body’s Immune System
What is a virus?

A strand of DNA surrounded by a protein coating.
 Viruses can only reproduce inside a living cell.
 Viruses take on many shapes from rod, round, bricks,
threads, bullets, and even robot like shapes.
How do viruses multiply?
In your notes draw a diagram that displays
how a virus multiplies. Label the stages of
the diagram.
 Structure of viruses are the same.


Viruses have two basic parts:
A
protein coat that protects the virus
 An inner core made of genetic material
How viruses and bacteria affect
your health?



Bacteria and viruses are known as infectious
diseases when they enter your body and make
you sick. (spread by contact with an infected
person, object, animal, or source)
Bacteria can be treated with antibiotics
(remember that it also kills the good bacteria
inside your body).
Viruses can’t be treated with antibiotics, rather
you are given a weakened strand of the virus
known as a vaccine and your body builds its own
treatment to the virus.
How can you prevent yourself from viral
and bacterial infections?
What is bacteria?



Bacteria are single celled organisms.
They are prokaryotes, meaning their genetic material in
the cell is not contained in a nucleus.
Bacteria take one of three shapes: spherical, rodlike, or
spiral.
Bacteria continued

Bacteria reproduce one of two ways; either asexually
(involves only one parent) by binary fission or sexually
(involves two parents) by conjugation.
What does bacteria look like?

Draw and label this diagram into your notes.
What are the bacteria kingdoms?
Eubacteria- Found in more common areas and are
larger.
2. Archaebacteria- Found in extreme conditions (hot
springs). The original bacteria that was on earth.
1.
What are the beneficial bacteria?




Antibiotics- Produce chemical to prevent the bad bacteria.
Saprophyte- Bacteria that breakdown dead material for food.
 Used in sewage treatment plants.
Nitrogen-Fixing Bacteria- Create usable nitrogen for plants.
Food Production- Milk, Yogurt, and Cheese.
What are the harmful bacteria?


Some bacteria cause disease and know as pathogens.
 Pathogen: Any organism that causes disease.
 Ex. Streptoccocus, Tetanus, Anthrax.
Pasteurization- Heating food to a temperature to kill that
bacteria that lives on it.
What is a protist?
Protist are eukaryotes (have a nucleus)
that can be classified as animals, plants,
or fungi.
 Always found in wet places.

How are protists and cells alike?




Protists are single celled or contain multiple cells.
Protists use cell division to multiply.
Protists and cells are eukaryotic.
Protists and cell can be both plant-like and animal-like.
How are protists and cells
different?




Most protists can move themselves from one place to
another.
Protists can be multi-celled.
Protists can be fungus-like.
Protists can reproduce sexually.
What are the types of Protists?

Three major types of protists:



Plantlike Protists
Animal-like Protists
Fungus-like Protists
What are the characteristics of
animal-like protists?



Animal-like protists are known as protozoan.
Animal-like protists are able to move from place to place.
Animal-like protists capture other organisms for food.
 Animal like protist are categorized by the way they
move:



Ciliates:Move using tiny hairs.
Flagellates: Move using a tail-like structure.
Move with pseudopods (an extension of cytoplasm)
What are the characteristics of
plantlike protists?



Plantlike protists usually don’t move.
Known as Algae.
Make their own food using photosynthesis.

There are six types of plantlike protists:
 Diatoms, dinoflagellates, euglenoids, red algae, green algae, and
brown algae.
What are the characteristics of
funguslike protists?


Funguslike protists have cell walls, and use spores to
reproduce.
Retrieve food through outside source.

The three types of funguslike protists are slime molds, water
molds, and downy mildews.
What are fungi?
Fungi have both characteristics of a plant
and animal. They are eukaryotes that
have cell walls, are heterotrophs that feed
by absorbing their food, and use spores to
reproduce.
 Fungi play important roles as
decomposers and recyclers on Earth, they
are food, and are used to fight diseases.

What are pathogens?



Pathogens are organisms that cause a disease.
Pathogens are spread through contact with an
infected person, object, or animal; or by soil,
food, or water.
Four types of pathogens are
 Bacteria
 Viruses
 Fungi
 Protists
How does the body fight off
pathogens?



The body has three lines of defense against
pathogens.
First line of defense is the skin, breathing
passages, and stomach. They act as a barrier
to pathogens, keeping them out or trapping and
killing the pathogen.
Second line of defense is the inflammatory
response. Here the body responds with fluid
and white blood cells. White blood cells leak
from the blood into the tissue and fight off the
pathogens.
Immune system continued

Third line of defense is the immune
response where the cells of the immune
system can distinguish between different
types of pathogens.
T-cells are sent out to identify the pathogen
(take a picture)
 B-cells produce the protein to fight off the
pathogen (build proteins)

What is AIDS and HIV?



AIDS (acquired immunodeficiency syndrome) is the
disease that is caused by the virus HIV (human
immunodeficiency virus).
HIV is the only virus in the world know to directly attack
the human immune system. It destroys the T cells of the
immune response, meaning the immune system can no
longer fight off a pathogen that enters the body.
HIV/AIDS doesn’t actually kill the person, it is another
pathogen that enters the body and kills the person.
HIV is an infectious disease that is spread from one
person to the next through bodily fluid contact. Meaning
an infected persons bodily fluids must come into contact
with the bodily fluids of an uninfected person.
What are active and passive
immunity?


Draw a Venn Diagram for this slide:
Passive immunity occurs when the antibodies for that
pathogen come form a source other than the person’s
body.


Immunity received from your mother when she is pregnant and
through breast milk.
Active immunity occurs when ones own immune system
produces the antibodies in response to the presence of a
pathogen.


Immune response-when you become sick and you body
naturally fights it off.
Vaccination-a weakened strand of a virus is presented in the
body and the body fights it off.
What are noninfectious diseases?

Noninfectious diseases are diseases that aren’t
caused by pathogens in the body therefore they
can’t be transmitted from one person to the next.
 Allergies
 Diabetes
 Asthma
 Cancer
 Heart disease
 Stroke