Kingdoms and Domains

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Kingdoms
and Domains
Biology 112
Outcomes:

The student will be expected to:



Develop a list of characteristics shared by living
things
Identify the general characteristics that
distinguish the members of each recognized
kingdom
Demonstrate an understanding that the
recognized kingdoms of living things represent a
diversity of organisms exhibiting extensive
variety in terms of form and function
Characteristics of Living Things



No single characteristic is enough to describe a living
thing
Some nonliving things share characteristics with living
things
All living things:
 Made up of units called cells
 Reproduce
 Are based on a universal genetic code
 Grow and develop
 Obtain and use materials and energy
 Respond to their environment
 Maintain a stable internal environment
 Taken a group, change over time
The Six Kingdoms of Life
 Prokaryotes




Used to be called Kingdom Monera
Eubacteria and Archaebacteria
Lack nuclei, mitochondria, and chloroplasts
as well as reproduce by binary fission
Been evolving for 3.5 billion years
 Eukaryotes


Protista, Fungi, Plantae, and Animalia
Been evolving for 2.0 billion years
The Three Domain System
 Scientists
have grouped organisms based
on how long they have been evolving
independently
 As a result, the domain has been
introduced as being even more inclusive
(larger and sharing less characteristics)
than the kingdom
 Domain Eukarya
 Domain Bacteria
 Domain Archaea
Domain Bacteria
 Unicellular
and prokaryotic
 Cells have thick walls that surround the
membrane made of peptidoglycan
 They may photosynthesize and some
require oxygen
 Examples
include Streptococcus,
salmonella, E. coli
Domain Archaea
 Unicellular
and prokaryotic
 Many can only survive in the absence of
oxygen
 Their cell walls lack peptidoglycan but
membranes contain a lipid that are not
found in any other organism
 Example:
Thermococcus litoralis
Domain Eukarya
 Consists
of the four remaining kingdoms
 Protista – displays the greatest variety
among its members
 Fungi – heterotrophs; most found on dead
and decaying matter
 Plantae – multicellular and
photosynthetic, non-motile, cell walls
contain cellulose (when they are present)
 Animalia – multicellular and
heterotrophic, no cell walls
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