Download The Three Domains of Life

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The Three Domains of Life
Arc________________
Eub_______________
Euk_________________
Each cell ____________ has unique characteristics. Prior to ___________, were
grouped together and called ________________________ - still see this used. Are
sometimes referred to as Monera. Advances in __________________ biology
identified ________________________________ as unique type of cells (Carl
___________, late 70’s, U of Illinois). They had been thought of as
________________. They have ___________ that is very different from
____________________ DNA.
Characteristics of Archaea
Archaea _________ like bacteria
o _________, spiral, and marble-like shapes like bacteria.
Like Bacteria they have __________________DNA
Archaea and bacteria share certain ______________, so they _____________
similarly in some ways.
Archaeans also share genes with _________________,
•Also have many genes that are completely ______________.
'archae' meaning ________________.
•Archaea are believed to be the _____________ _____________ forms of life on Earth.
Called “_______________________” due to the extreme conditions they live in.
o similar to the conditions of __________ Earth
•________________ which contain an environment where Archaea might survive
include Venus, the past environment of Mars, Jupiter, Saturn, and Jupiter's moon Io.
Extremeophiles
Live at ________ ˚C or greater
o hot springs, sea vents
In extremely ______________ or _______________ conditions
o Like the _______________ tracts of cows, termites, and marine life
o They produce ________________. They are found in __________ muds
of marshes and sea floors and in ________________ deposits deep
underground
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Archae do not require ________________ or _________________.
They absorb __________, ______ , or ___________ and give off _______________
Gas as a waste product.
Archaea: Morphology
•Size < one _______ (1μ)
•___________ vary
•spherical (coccus)
•rod-shaped (bacillus)
•hair-like
•triangular
•square
•May have one or more _______________
•If __________________ flagella are present, they attach on __________ side.
•No internal __________________
•DNA is a _________ loop called a _________________
•_______________ are unique
•"transfer RNA” are important in _____________ the message of DNA and in
building proteins.
•__________________ are similar to eukaryotes.
ARCHAEA Cell Structure
•Have an outer ______________________
•Within the membrane is the ___________________
•Around the outside of nearly all archaeal cells is a cell _________
•a semi-rigid layer that helps maintain its ___________ and chemical _________
•All three structures are biochemically ____________ to Arcahaea
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EUBACTERIA
•True ___________
•Found in the _______, _________, _________ and on most moist surfaces
•Includes the spirochetes, gram-positive bacteria and cyanobacteria.
Eubacteria shapes
•Their cells are either ______________, ____________-shaped or ___________
•_______________ are spherical, ______________ are rod-shaped and
____________ are spiral.
Bacteria live ____________________ or are found in _________________.
•Clusters are________________ based on the ___________________ of the bacterial
cells. Using ________ as an example:
•__________________ are in sets of two
•____________________ – a number of cells clustered together (like grapes)
•______________________ – a number of cells arranged in chains
Eubacteria Nutrition
 _________________________ use the sun’s energy and manufacture sugars.
 _________________________ need carbon dioxide to obtain energy from inorganic
substances.
_______________________________ are unique and use light to generate energy
but must obtain carbon in organic forms.
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_______________________________ use organic molecules such as sugar for
energy.
Eubacteria Morphology
•Most vary in size from 1.25 _____ to 10______
•Largest know is _________ Thiomargarita namibiensis
•Have ________ cell walls and a ____________
•May have ______________
•Have ______ – extensions of cell wall used to touch/exchange material with other cells
•No _______________ or membrane bound ________________
•Have a _______________ __________ – circular nucleotides – _____________.
Label the following diagram:
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