Transcript Things that make you sick!

Things that make you sick!
Viruses, Bacteria, and Fungi!
Oh, my!
Vocabulary
Pathogen--infectious agent (germ); a
microbe such as a virus, bacterium,
prion, or fungus that causes disease in
its animal or plant host
 Mutagen--is a physical or chemical
agent that changes the genetic material

Vocabulary
Carcinogen--any substance that is an
agent directly involved in causing
cancer
 Resistance--is a type of drug resistance
where a microorganism is able to
survive exposure to an antibiotic caused
by genetic mutation in bacteria
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Vocabulary
Transmission--how diseases spread
from person or object to another
 Carrier--is a person or other organism
that has contracted an infectious
disease, but who displays no symptoms
 Vector--is any agent (person, animal or
microorganism) that carries and
transmits an infectious agent

Methods of Transmission

Contact with an infected person
– Touching, hugging, kissing
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Contact with a contaminated object
– Cups, door knobs, lockers
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Contact with an infected animal
– Ticks, dogs, mosquitoes
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Contact with environmental sources
– Food, water, soil
Pathogens

Parasite--An organism that lives in or on
a host and causes it harm
– Worms, mites, ticks
Pathogens
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Bacteria are only considered pathogenic if
they form a parasitic relationship with a host
organism
 Cells are contained within a cell membrane
but lack membrane bound organelles
 Genetic material is present as single, circular
chromosome
 Treated with antibiotics
Common Bacterial Shapes

Cocci--Sphere
shaped
 Bacilli--Rod shaped
 Spirillum--Spiral
shaped
Pathogens

Virus--a small infectious agent that can
replicate only inside the living cells of
organisms
 Viral infections in animals provoke an immune
response that usually eliminates the infecting
virus
 Vaccines are used to stimulate the immune
system to recognize invading viruses
Common Viral Structures
Genetic material--DNA or RNA, usually
RNA
 Protein coat--Protects the virus
 Membrane envelope--Surrounds the
virus
 Membrane proteins--Attaches to host
cells and is host specific
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Common Viral Structures
Viral Replication

Viruses reproduce by attacking and
taking over a cell’s normal cell division
Pathogens
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Fungi are eukaryotes that have cell
walls, are heterotrophs that feed by
absorbing their food, and use spores to
reproduce
– Includes yeast, molds, and mushrooms
Fungi Usages
Drugs--produces antibiotics
 Food--yeast in bread, cheese culture
 Bioremediation--breaks down materials
 Pathogenic--skin infections (ringworm,
athlete’s foot)
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Common Fungi
Pathogen
Protists are organisms that cannot be
classified as animals, plants, or fungi
 Animal-like protists are called protozoan
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– Amoeba
– Paramecium
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Parasitic protozoan feed on cells and
body fluids
Protists