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Patterns of Life Chapter 4
Patterns of LifeChapter 4
Section 4.1:Characteristics of Life
pg. 102-107
Activity
Read pages 100 & 102.
In a group of 2 people (ideally the person you sit beside), do the “Thinking Lab” activity on page 103.
Characteristics of Living Things1. Are organized systems made up of
one or more cells, tissues or organs
2. Metabolize matter and energy
3. Interact with their environment and
are homeostatic ( they maintain an
internal environment that is
different from their surroundings)
4. They grow and develop
5. They reproduce themselves
6. Are adapted to their surroundings
To date, biologists have named 1.5 million different species.
There are at least 20 million more species waiting to be discovered!!
In the beginning…
• 2000+ years ago, Aristotle classified organisms into two Kingdoms: Plantae & Animalia
• 1866 Ernst Haeckel developed the Kingdom Protista (micro-organisms)
• Later on, three more were developed:
– Fungi (do not photosynthesize)
– Bacteria (lack nucleus & other organelles)
– Archaea (bacteria that live in extreme conditions)
The 6 Kingdoms of Living Things
1. Kingdom Bacteria
2. Kingdom Archaea
3. Kingdom Protista
4. Kingdom Fungi
5. Kingdom Plantae
6. Kingdom Animalia
Cellular Structure
Prokaryotes:
Organisms composed of
cells who lack a true
nucleus and most other
organelles eg. Bacteria and
Archaea
Eukaryotes:
Organisms composed of cells,
which contain true nuclei and other
types of membrane-bound
organelles eg. Fungi, Protists,
Plants, Animals
Fossil evidence shows that the first forms of life on Earth were prokaryotic cells (3.5 billion years ago)
The first eukaryotes did not appear until 1.5 billion years ago.
The first multicellular forms of life appeared 700 million years ago.
Three Domains of Life
Scientists have discovered that prokaryotes are far more
diverse than anyone had previously suspected.
The molecular biology of bacteria and archaea, show that
they are very different from one another.
As a result, biologists have created a new level of
classification above Kingdoms known as DOMAINS. The
three domains are…..
Domain Bacteria
(Kingdom Bacteria)
Domain Archaea
Kingdom Archaea
Domain Eukarya
Kingdom Protista
Kingdom Fungi
Kingdom Plantae
Kingdom Animalia
Section 4.1:Review Questions
Page 107 #’s 1-5, 7 & 8
1. List examples of classification systems you use every day.
Phone book, Internet search engine, library cataloguing system, TV listings, etc…
2. Would a group identified as “flying animals” be useful to a biologist? Explain why or why not.
Flying animals would put insects, birds and several mammals into the same category. This classification would be helpful to some degree, but would not provide information about the relatedness of such a broad range of organisms.
3. Why is it beneficial for all scientists to use the same system to classify living things?
A common classification system allows for ease of communication.
4. What criteria does a biologist use to distinguish between a living and a non-living thing?
Biologists consider characteristics such as cellular organization, metabolism, interaction with internal and external environment, growth, development, reproduction and adaptation. 8000
5. You have discovered an unknown organism while on a field trip. You think it is a new species of protist. How could you test to identify this species as a protist? What data would you need to have to classify it in the Kindom Protista?
By determining whether the cell is prokaryotic or eukaryotic would rule out Bacteria and Archaea.
7. Describe and explain briefly, in the form of a paragraph or graphic organizer, key stages in the development of the six-kingdom classification system.
As the number and diversity of known organisms increased, and as scientists learned more about their anatomy and behaviour, they had to reassess and revise their classification criteria.
8. You discover an unusual organism growing on the bark of a dying tree. Later, in the laboratory, you look at some of its cells under a microscope. It is a multicellular organism with eukaryotic cells but no chloroplasts. To what kingdom does it belong?
It is a fungus if it possesses a cell wall, and an animal cell if it does not. Given where it grows, it is most likely a fungus.
