Diversity of Living Things Objectives: 1. Explain how multi-cellular organisms evolved from single cellular organisms 2. Differentiate between prokaryotic and eukaryotic organisms 3. Explain what taxonomy is. 4. Describe distinguishing characteristics of organisms in each of the six kingdoms
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Diversity of Living Things Objectives: 1.Explain how multi-cellular organisms evolved from single cellular organisms 2.Differentiate between prokaryotic.
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Diversity of Living Things
Objectives:1. Explain how multi-cellular organisms evolved from single cellular organisms
2. Differentiate between prokaryotic and eukaryotic organisms3. Explain what taxonomy is.
4. Describe distinguishing characteristics of organisms in each of the six kingdoms
How is All Life on Earth Related?
• All of life is made up of the same macromolecules.
(What are the 4 macromolecules of life?)• All of life uses DNA to pass on genetic
information from one generation to the next.
• All of life is made up of cells.
Figure 1.9 Life’s Calendar
•First cells arose about 3 billion years ago.
•For 2 billion years, life consisted of single cells—prokaryotes. –These cells were in the oceans,
protected from UV radiation.
•Photosynthesis evolved about 2.5 billion years ago.
The first photosynthetic cells were similar to cyanobacteria.
Consequences of photosynthesis•O2 accumulated in the atmosphere•Aerobic (with oxygen) metabolism began
•Ozone layer formed—allowed organisms to live on land
Eukaryotic cells evolved from prokaryotes.- They contained organelles —
membrane bound compartments with specialized functions:
• Nucleus• Chloroplast
Diversity
• So how did the rest of Earth’s organisms get here?
• Evolution gives rise to diversity• Over time organisms evolve and change into
more complex organism• I.e.: Single cell Prokaryotes multi cell
Eukaryotes
Taxonomy: the science of identifying and classifying all organisms - both living and non-living.
Organisms are identified by observing physical characteristics, behaviour and geographic location.
• Biological classification: The grouping of organisms in to groups/categories, based on their physical and evolutionary characteristics or relationships.
• Carl Linnaeus is credited with devising a naming system for all living things, called binomial nomenclature.
– Ex. Castor (meaning Beaver) canadensis (meaning ‘from Canada’): Genus name, species name
– Both underlined or italicized to indicate that they are Latin
• Based on the idea, that the more features organisms have in common, they closer their relationship
Kingdoms• Linnaeus created a system to further group
organisms in to different levels (Tomorrow)• The first, most general level was kingdom.• Originally there were only two Kingdoms
– Plants and Animals
• Now-a-days there are six commonly recognized Kingdoms– Eubacteria, Archaebacteria, Protista, Fungi, Plantae and
Animalia
The Six Kingdoms
1. Eubacteria (Bacteria)
2. Archaebacteria (Archaea)
3. Protista
4. Fungi
5. Plantae
6. Animalia
PROKARYOTIC
EUKARYOTIC
Your Task
• In groups of 4 or 5• Use your textbook to research and find the
required information about your given Kingdom.
• Once you have completed your research and filled in your table please fill in your section of the overhead located up front.
Plenary• Answer the following questions...1)What Kingdoms contain Eukaryotic organisms?2)What Kingdoms contain Prokaryotic organisms?3)What is the major difference between Prokaryotic
and Eukaryotic organisms?4)What distinguishes Eubacteria from Archaea?5)What distinguishes Plants from Fungi?
Thinking...How did Eukaryotic organisms evolve from
Prokaryotic organisms?
Homework...
• Read page 326-331• Answer questions 2, 3, 4, 5, 6• Read through worksheet and answer
questions.
Extra questions…
1. What is taxonomy? 2. Explain how the taxa are arranged in a hierarchy.3. List the 6 kingdoms and three characteristics of
each.4. Why do you think that biologists originally placed
fungi within the plant kingdom?5. List the seven main taxonomic ranks/levels of
classification in order from most inclusive to least inclusive.
Taxonomic Rank
Objectives:1. Explain what the term taxonomy means.2. State the 7 levels of taxonomic classification
Quiz
1. What Kingdoms contain single celled organisms?2. What Kingdoms contain multi-celled organisms3. What is the major difference between Prokaryotic
and Eukaryotic organisms?4. Name the three ‘Domains’ and the Kingdoms in each
Domain.Bonus: List, in order the major levels or classification
(Start with Kingdom.).
The Seven Levels of Taxonomic Classification:
KINGDOM
PHYLUM
CLASS
ORDER
FAMILY
GENUS
SPECIES
most inclusive taxon
least inclusive taxon
King Philip Could Only Find Good Shoes
Ex: Taxon Human Bald EagleKingdom Animalia AnimaliaPhylum Chordata ChordataClass Mammalia MammaliaOrder Primates CarnivoraFamily Hominidae OdobenidaeGenus Homo OdobenusSpecies Homo sapiens Odobenus rosmarus
Taxonomic Levels
• Taxon: a category or level used to group or classify organisms with certain shared characteristics.
• Ie: all species in phylum Chordata have a backbone• Ie: all members of class Mammilia are warm-
blooded• Taxonomic Rank: The levels of classification in a
hierarchy (The most basic rank is that of species, the next most important is genus, and then family)
Human Nine-Banded Armadillo Kingdom: Animalia Animalia
Phylum: Chordata Chordata
Class: Mammalia Mammalia
Order: Primata Xenarthra
Family: Hominidae Dasypodidae
Genus: Homo Dasypus
Species: sapiens novemcinctus
Name: Homo sapiens Dasypus novemcinctus
Phylogeny and Dichotomous Keys
Objectives:1. Explain what phylogeny means.2. Explain what a dichotomous key is used for and
demonstrate how to use one to identify an unknown organism.
Quiz
• Answer the following questions...1)What is taxonomy?2)What does hierarchical classification mean?3)What does binomial nomenclature mean?
Evolution• Today scientists believe that organisms have
changed over time.Based on Darwin’s theory of evolution, which states that all living things have descended from a common ancestor.
• Phylogeny: The history of the evolution of a species or a group of organisms (evolutionary relationships)– Speciation – Genetic diversity– Species diversity
Phylogeny(More on this later)
• The study of the evolutionary relationship between and among species
• Often shown in the form of a phylogenetic tree which is a diagram that shows the evolutionary relationship between species
• DNA sequencing studies reveals that some genes in archaebacteria are more closely related to human genes and other eukaryotes than to those of eubacteria.
Three-Domain system of classification may better reflect the history of life.
Domain: the highest taxonomic level (above kingdoms) – each domain is genetically distinct
Classified into three domains
Based on what you have learned so far,… describe the most significant differences between the three domains of life. Why are the Eubacteria and Archaea difficult to distinguish?
Domain Eubacteria: Kingdom Eubacteria
Domain Archaea: Kingdom Archaea
Domain Eukaryotes: Kingdom Protista
Kingdom Animalia Kingdom Plantae Kingdom Fungi
NB: What makes something a species?
- can reproduce and produce fertile offspring
Try: dichotomous key activity (complete for homework)
These spiders look different but are the same species: can reproduce and have fertile offspring.
So how do we classify all these different organisms???
Dichotomous Keys
4.1 Life on EarthFrom antelopes to zebras - each type of animal is a species. There are more than
two million species.
Many more are yet to be discovered and scientistsestimate there could be up to 30 million different types of
living things!
Are these different species?
We can't tell without seeing if their offspring are fertile
4.1 Different species
Blackbuck Pronghorn
4.2a Finding what you want
Aisle 7
milk and dairy
Aisle 8
bread and cakes
Aisle 9
fruit
Where would you find these:
strawberry yoghurt, raspberries, fruit cake, clementines
Sorting things into groups is
classification
Classification key…
• A classification key can be used to help you classify an organism based on its characteristics.
Dichotomous Key: A two-part key used to identify living things.
The Key
1. A) Has hairB) Doesn’t have hair
2. A) Has feathersB) Doesn’t have feathers
3) A) Uses gillsB) Uses lungs
4) A) Has smooth skinB) Has scales
• Mammal• Go to 2• Bird• Go to 3
• Fish• Go to 4• Amphibian• Reptile
All Vertebrates
Has Hair No Hair
Feathers
No Feather
sUses Gills
Uses Lungs
Smooth Skin
Scales
Mammal
Bird
Fish
Amphibian Reptile
Your Task
• Turn to page 332/333• Complete activity• Answer Analysis questions on page 333
• Evaluation and Synthesis: Create your own Dichotomous Key to identify the insects shown.
H/W: Complete handout on Using a Dichotomous Key
Plenary1) What does phylogeny mean?2) What are the three domains?3) What is the classification of organisms into these
domains based on?4) What is a taxon?5) What are the 7 ranks of taxonomy?6) What is the most specific taxon and how are
organisms in this group related?7) What tool can we use to help identify or classify