The cell is the fundamental unit of life. All living things are made up of one or more cells.
All Living Organisms can be Divided into 3 Domains as Follows:
I. Archaea
i. Used to be considered bacteria, but now seen as a distinctly different cell having features in common with both prokaryotic and eukaryotic cells. ii. They are thought to be the first life forms on Earth.
II. Prokaryotic
i. More primitive – simpler - smaller
ii. Does not have compartmentalization – no membrane-bound organelles or nucleus
III. Eukaryotic
i. There are 4 types of eukaryotic organisms
1. Plants
2. Animals
3. Fungi
4. Protists
ii . The characteristics of eukaryotic cells are as follows:
1. Has nucleus
2. Has membrane-bound organelles
3. Evolved much later
4. More complex - larger
I. Archaea
i. Used to be considered bacteria, but now seen as a distinctly different cell having features in common with both prokaryotic and eukaryotic cells. ii. They are thought to be the first life forms on Earth.
II. Prokaryotic
i. More primitive – simpler - smaller
ii. Does not have compartmentalization – no membrane-bound organelles or nucleus
III. Eukaryotic
i. There are 4 types of eukaryotic organisms
1. Plants
2. Animals
3. Fungi
4. Protists
ii . The characteristics of eukaryotic cells are as follows:
1. Has nucleus
2. Has membrane-bound organelles
3. Evolved much later
4. More complex - larger
Cells are divided into two broad categories;
Prokaryotic Cells and Eukaryotic Cells.
Prokaryotic Cells
Prokaryotic organisms consist of only a single prokaryotic cell. Prokaryotic organisms include bacteria and archaea. Prokaryotic organisms were the first life-forms on Earth. They existed alone for millions of years before the first eukaryotic organisms evolved. Prokaryotic cells are smaller and less complex than eukaryotic cells.
Some of the key features of prokaryotic cells are as follows:
PROKARYOTIC CELLS
Some of the key features of prokaryotic cells are as follows:
PROKARYOTIC CELLS
- Have no nucleus
- Have no membrane-bound organelles
Eukaryotic Cells
Eukaryotic cells include plant cells and animal cells.
Some of the key features of eukaryotic cells are as follows:
EUKARYOTIC CELLS
EUKARYOTIC CELLS
- Have a nucleus (that contains DNA)
- Have membrane-bound organelles
- DNA is in the form of a double-helix that is organized into chromosomes
Eukaryotic Organisms Include:
1. Plants 2. Animals 3. Fungi 4. Protists |
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The ecological role of an organism depends upon how that organism gets its energy and its relationship with other organisms and the environment.
Autotrophs / ProducersAutotrophic organisms have the ability to make food out of inorganic substances (like sunlight or inorganic chemicals). For example, plants use sunlight to obtain the energy they need to grow and survive through the process of photosynthesis. Autotrophs are also called "producers", because they produce their own food.
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Heterotrophs / Consumers
Heterotrophic organisms are also called "consumers", because they must consume other organisms to obtain the energy they need to grow and survive.
Decomposers
Symbiosis
Mutualistic Symbiosis - Mutualistic symbiosis is an enduring interspecies interaction that benefits both species.
Parasitic Symbiosis - Parasitic symbiosis is an enduring interspecies interaction that benefits one species, yet harms the other.
Commensalistic Symbiosis - Commensalistic symbiosis is an enduring interspecies interaction that benefits one species, yet has no affect the other.