Transcript Pathogens: An organism that causes disease.

Pathogens: An organism that causes
disease. (Chp. 18/chp.39) see p.550
Bacteria
Protists
Pathogens
Fungi
Viruses
Types of Diseases
Contagious…if it spreads quickly
• Non-communicable
Disease: cannot be
transmitted from one
person to another
• Heart attach
• Depression
• Stroke
• Hypertension/hypo.
• Cancer
• Genetic disorders (only
to their children)
• Communicable Disease:
can spread from one
person to another
• Diarrhea
• Pneumonia
• Tuberculosis (TB)
• Sexually transmitted
diseases (STD’s)
Bacteria
• Unicellular and everywhere
• Some damage cells and tissues
• Others release Toxins: poisons that travel
through the body and may cause diseases
• There are environmental toxins:
Lead and Mercury
Other toxins:Botulism> improperly prepare food
Diseases Caused by Bacteria
Disease
Bacterium
Effect on Body
Strep Throat
Streptococcus
Fever, sore throat
swollen neck
glands
Tuberculosis
Mycobacterium
Fatigue, weight
loss, mild fever,
chronic cough
Tetanus
Clostridium tenani
Muscle spasms,
paralysis, death
Lyme Disease
Borrelia burgdorferi Rash at site of tick
bite, fever, chills
Bacterial Meningitis Neisseria
meningitidis
High fever,
headache, stiff
neck, nausea
Diphtheria
Sore throat, lowgrade fever
Corynebacterium
diphtheria
Viruses: Nonliving..Must have a
LivingHost
• Consist of genetic material enclosed in a protein
coat (Capsid [head], nucleic acid, Sheath, Tail)
• Bacteriophage (phage): a virus that infects a
bacterium. The virus will attach its legs to a cell
and then inject its genetic material into it. The
virus takes control of the bacterial cell and directs
it to produce viral material. A single infected cell
may replicate thousands of viruses.
A typical Bacteriophage, a type of virus
Protein coat
Attaches to a cell
Viruses Cause….
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HIV
Influenza
Chickenpox
Colds
Measles
Rabies
Viral Replication Cycles p. 478/479
• (1)Lytic Cycle: immediately takes over killing
the host cell
• (2) Lysogenic Cycle: does not kill host cell
immediately integrates its genetic material
with the host cell…creates a provirus…..sits
dormant….then one day takes over the host
Viral Replication Cycles