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

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

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.

· ______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: