I will classify organisms based on the distinguishing
characteristics of the domains and kingdoms of living organisms. I
will describe how and why organisms are hierarchically classified
and based on evolutionary relationships. SC.912.L.15.6 Discuss
distinguishing characteristics of the domains and kingdoms of
living organisms. (AA) 15.4Describe how and why organisms are
hierarchically classified and based on evolutionary relationships.
What are we learning today? BenchmarksLearning Objectives
Slide 3
WHY DO WE ORGANIZE THINGS? Classify, or organize, the following
terms into groups Classify, or organize, the following terms into
groups. South America Monroe El Portal Asia D ade Montana Canada
Haiti North America Miami Aventura Palm Beach Mexico United States
Africa France Alabama Florida Europe Illinois Alaska Hawaii Broward
Martin Hialeah Little Haiti
Slide 4
WHAT IS THE ESSENTIAL QUESTION? Try to imagine the problems
faced by the biologists of several hundred years ago as they tried
to find patterns in the vast diversity of life. What are some
similarities that you might use to try to put the following
organisms into related groups?
Slide 5
Why do biologists classify? Biologists have identified and
named about 2 million species so far. Scientists estimate that
there are about 8 million additional species yet to be discovered.
Taxonomy is the discipline where scientists classify and assign
each organism a universally accepted name.
Slide 6
How Has Classification Changed Since the 1700s?
1700180019002000 1753 Linnaeus introduced his two-kingdom system
which included Plantae and Animalia 1938 American Biologist Herbert
Copeland argued that all prokaryotes deserved their own kingdom,
Monera 1977 Research by Carl Woese led scientists to split Monera
into two kingdoms: Eubacteria and Archaeabacteria 1866 German
biologist Ernst Haeckel proposes moving all single-celled organisms
to the Kingdom Protista 1959 American ecologist Robert Whittaker
proposed that fungi should be placed in their own kingdom because
of how they feed
Slide 7
We Classify Organisms into Kingdoms Based on 4 Criteria 1. Is
its body made up of 1 cell or many cells? 2. Does its cell(s) have
a nucleus or not? 3. Does the organism make its own food or is it a
consumer? 4. Does it have any other special characteristics that
set it apart from other organisms?
Slide 8
The cell is the basic structural and functional unit of all
known living organisms. It is the smallest unit of life that is
classified as a living thing. Organisms can be classified as
unicellular (its whole body is a single cell; includes bacteria,
protista, some fungi) Or multicellular (many cells make up its
body; includes some fungi, all plants and all animals) WHAT ARE THE
DIFFERENT TYPES OF CELLS?
Slide 9
WHAT ARE PROKARYOTES AND EUKARYOTES?
Slide 10
Both eukaryotes and prokaryotes have a cell membrane genetic
material (DNA) ribosomes cytoplasm HOW ARE PROKARYOTES AND
EUKARYOTES SIMILAR?
Slide 11
Nucleus is present Many membrane-bound organelles Many 2-1000
um in size Evolved 1.5 billion years ago MORE RECENT All other
kingdoms (animal, plant, fungi, and protist) Nucleus is absent No
membrane-bound organelles Most 1-10 um in size Evolved 3.5 billion
years ago FIRST LIVING THINGS Only bacteria and archaeabacteria HOW
DO PROKARYOTES AND EUKARYOTES DIFFER? Prokaryotes Eukaryotes
Slide 12
WHAT IS THE THREE-DOMAIN SYSTEM? The domain is the largest
category of classification. The three domains are: Eukarya,
Bacteria, and Archaea.
Slide 13
SUMMARY OF CHARACTERISTICS OF THE SIX KINGDOMS WHICH VERY
IMPORTANT CHARACTERISTIC IS MISSING??
Slide 14
Corresponds to the domain Archae. Unicellular and prokaryotic
organisms live in some of the most extreme environments on our
planet. Many of these bacteria can survive only in the absence of
oxygen. WHAT MAKES UP THE KINGDOM ARCHAEABACTERIA?
Slide 15
WHAT IS THE KINGDOM EUBACTERIA? Corresponds to the domain
bacteria. Members are unicellular and prokaryotic. Cells have a
thick, rigid cell wall containing peptidoglycan. Ecologically
diverse, ranging from free-living soil organisms to deadly
parasites. Some need O 2, other are killed by it.
Slide 16
WHAT MAKES UP THE DOMAIN EUKARYA? Consists of all organisms
that have a nucleus. Composed of protists, fungi, plants, and
animals.
Slide 17
Algae are plant-like because they do photosynthesis. Simpler
than plants Live in lakes, streams, rivers, ponds, oceans. Algae is
autotrophic. Food source for many aquatic organisms form the base
of the food web Some protozoans have properties of both plants and
animals. Live in water, soil, and in the bodies of animals. Most
are harmless, but a few cause disease. Have different methods of
moving: Flagellum Cilia Pseudopods Animals-Like Protists Plant-Like
Protists
Slide 18
WHAT IS IN THE KINGDOM FUNGI?
Slide 19
WHAT ARE THE CHARACTERISTICS OF THE KINGDOM FUNGI? Eukaryotic
Heterotrophs Cell wall with chitin Most feed on dead or decaying
organic matter. Fungi secrete digestive enzymes into their food
source, before absorbing the smaller food molecules into their
bodies. Most multicellular, some are unicellular
Slide 20
WHAT IS THE KINGDOM FUNGI? Fungi release special chemicals on
dead plant and animal matter. These chemicals break down, or
decompose, the dead matter. This decomposed matter is later
absorbed by the fungus or the soil.
Slide 21
WHAT ORGANISMS ARE IN THE KINGDOM PLANTAE?
Slide 22
What organisms are in the Kingdom Plantae? Trees, grasses,
ferns, and mosses. Nonmotile, meaning they can not move from place
to place. They are photosynthetic autotrophs. Multicellular Cell
walls contain cellulose
Slide 23
WHAT MAKES UP THE KINGDOM ANIMALIA?
Slide 24
WHAT ARE THE CHARACTERISTICS OF THE KINGDOM ANIMALIA? Eukaryote
Multicellular Heterotroph No cell wall or chloroplasts
Slide 25
What is the three-domain system? All organisms evolved from
cells that formed over 3 b.y.a. Domain Archaea corresponds to the
Kingdom Archaebacteria Domain Bacteria corresponds to the Kingdom
Eubacteria Domain Eukaria includes the Kingdoms Protista, Fungi,
Plantae, and Animalia
Slide 26
TAXONOMY AND CLADISTICS Topic 9: Day 2 SC.912.L.15.5 Explain
the reasons for changes in how organisms are classified.
Slide 27
Explain the difference between evolutionary classification and
Linnaean classification. Analyze a cladogram to recognize the
concepts of common ancestry and degrees of evolutionary
relationship. Describe how DNA and RNA can help scientists
determine evolutionary relationships SC.912.L.15.4 Describe how and
why organisms are hierarchically classified and based on
evolutionary relationships. SC.912.L.15.5 Explain the reasons for
changes in how organisms are classified. What are we learning
today? BenchmarksLearning Objectives
Slide 28
How will you classify the following organisms?
Slide 29
How are Linnaean and evolutionary classification different?
Linnaeus grouped species into larger taxa, mainly according to
visible similarities and differences. This approach can cause
problems. The goal of evolutionary biology is to group species into
larger categories that reflect lines of evolutionary descent,
rather than overall similarities and differences. Inspired by
Darwins ideas about descent with modification
Slide 30
What is cladistic analysis? Modern evolutionary classification
uses a method called cladistic analysis. Cladistic analysis
identifies and considers only those characteristics of organisms
that are evolutionary innovations. Traits that appear in recent
parts of a lineage but not in its older members are called derived
characters. Derived characters can be used to construct a
cladogram, a diagram that shows the evolutionary relationships
among a group of organisms.
Slide 31
How can I read a cladogram? A speciation event, in which an
ancestral lineage branches into two new lineages, is the basis for
each branch point, or node. Each node represents the last point at
which the new lineages shared a common ancestor. The bottom, or
root, of the tree represents the common ancestor shared by all
organisms on the cladogram.
Slide 32
How can I read a cladogram? A cladograms branching patterns
indicate degrees of relatedness among organisms. Because lineages 3
and 4 share a common ancestor more recently with each other than
they do with lineage 2, you know that lineages 3 and 4 are more
closely related to each other than they are with lineage 2.
Likewise, lineages 2, 3, and 4 are more closely related, in terms
on ancestry, with each other than any of them is to lineage 1.
Slide 33
Collaborative Activity: Construct a Cladogram Purpose: In this
activity, you will ll in a cladogram for methods of transportation.
Problem Statement: How can methods of transportation be organized
using a cladogram?
Slide 34
Collaborative Activity: Construct a Cladogram Purpose: In this
activity, you will construct a cladogram to classify a group of
animals. (Pag. 520) Backbone Legs Hair
Slide 35
Collaborative Activity: Interpreting a Cladogram This cladogram
shows the evolutionary history of cats. 1. What are the derived
characters in this cladogram? 2. Is hair a derived character of
mammals? 3. Is amniotic egg a derived character of mammals? 4. For
which clade is retractable claws a derived character? 5. Why is
four limbs a derived character for clade tetrapoda, but a primitive
character for all the other clades?
Slide 36
How are DNA sequences used in classification? Similarities in
DNA can be used to help determine classification and evolutionary
relationships. The more similar the DNA sequences of two species,
the more recently they share a common ancestor, and the more
closely they are related in evolutionary terms. The more two
species have diverged from one another, or changed in comparison to
one another during evolution, the less similar their DNA will
be.
Slide 37
How are DNA sequences used in classification? 1. According to
the figure, which species is most closely related to red pandas? 2.
Biologists had previously classified giant pandas together with
raccoons and red pandas. What did DNA analysis reveal about giant
pandas and bears? DNA evidence suggests that that the giant panda
shares a common ancestor with bears than with either red pandas or
raccoons.
Slide 38
The Linnaean classification system is based solely on physical
characteristics. How has the classification of organisms changed
since Linnaeus developed his taxonomy system? In your answer:
explain how cladistics differs from Linnaean taxonomy. (5 pts.)
explain how new technologies in molecular biology and DNA research
have affected the Linnaean classification system. (5 pts.) What is
the essential question?