Transcript WELCOME TO THE WONDERFUL WORLD OF BACTERIA

BACTERIA
• ______________: single-celled organisms
that lack a nucleus
Bacterial Kingdoms
(formerly Monerans)
• Divided into TWO Kingdoms________________- “ancient bacteria”
________________- “good/true bacteria”
ARCHAEBACTERIA
• Characteristics
– Most live in ___________________________
– Cell wall does _____ contain _____________
– DNA sequence similar to ________________
(possible ancestor?)
Types of Archaebacteria
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EXTREMOPHILES
Methanogens- produce _________
Halophiles- live in ________ conditions
Thermophiles- live in high ____________
Etc.
EUBACTERIA
• Live ______________________________
• Cell wall contains ___________________
• Wide array of characteristics
Types of Eubacteria
• ____________: cell wall
mainly peptidoglycan
– Appear ____________
when stained
• ____________: cell wall
of _______ peptidoglycan
with second layer of lipids
and carbohydrates
– Appear ____________
when stained
How are bacteria identified?
• Shape:
– Bacilli- _______
– Cocci- _______
– Spirilla- ______
– *Strepto- ________
– *Staphylo- _______
How are bacteria identified?
• Cell Walls
– Is peptidoglycans present?
• Yes- ______________________
• No- _______________________
How are bacteria identified?
• Movement
– Some have ____________________
– Some glide, spiral, etc.
– Others don’t move on own
How are bacteria identified?
• Energy obtaining methods
– _____________________- make own food
• _____________________- use light
• _____________________- use inorganic materials
– _____________________- take in food
– _____________________- need light and a
nutrient source
How bacteria are identified?
• Energy releasing processes:
– Cellular respiration: requires Oxygen
(__________________________)
– Fermentation: no Oxygen used
(___________________________)
– Some can survive with or without oxygen
(___________________________)
How are bacteria identified?
• Reproduction & Growth:
– ____________________- double in size,
replicates DNA, splits into two (asexual)
Reproduction cont’d
– ________________________- bridge forms
between two cells and genes are transferred
Conjugation
– _____________________- thick wall around
DNA can remain dormant until conditions are
favorable
VIRUSES
• Virus- Latin for “_______________”
• Smaller than bacteria
• ___________ living!
Structure of a Virus
• Infectious agent made up of a core of
______________(DNA or RNA) and a
_______________(capsid)
Why not living?
• Viruses can’t ___________ on their ownthey must use a host’s cells
• Not made of ___________
• Cannot maintain _________________
Replication (Reproduction)
• 2 Types of Replication:
– __________ Cycle
– __________ Cycle
Lytic Cycle
• Virus enters the cell, makes copies of
itself, and causes the cell to burst
Steps of Lytic Cycle
– Virus attacks cell and ___________________
– DNA forms a circle
Steps of Lytic Cycle cont’d
– Viral DNA commands host cell to make
__________________
Lytic Cycle Steps cont’d
– Cell _____________ and releases viruses to
invade more cells
– *Symptoms of disease show
Lysogenic Cycle
• Virus embeds its DNA into the host’s DNA,
both DNAs are replicated
• ________________- viral DNA that is
embedded into host’s DNA
• *Symptoms of disease do not show at this time
Types of Viruses
• _____________- virus that infects bacteria
Types of Viruses- cont’d
• _____________- contain RNA as genetic
code (HIV & AIDS, some cancer)
RNA
• _________________- cause cancer in
animals (disrupt controls over cell growth)
Not quite a virus, but…
• ___________- “protein infectious particles”
– Act like a virus, but…
– Do not contain any ________, only ________
• Usually only affects _______________
• ___________– Act like a virus, but…
– Has ________, but no ___________
• Usually only affects _________________
Protection from viruses- HOW?
• PREVENTION!
– Good hygiene
– ______________- weakened or “killed”
viruses or viral particle
• Inject into body to build up immunity