living things what is life? classifying organisms domains and kingdoms the origin of life table of...
TRANSCRIPT
Living Things
What Is Life?
Classifying Organisms
Domains and Kingdoms
The Origin of Life
Table of Contents
Living Things
Life Comes From Life
Francesco Redi designed one of the first controlled experiments. In his experiment, Redi showed that flies do not spontaneously arise from decaying meat.
- What Is Life?
Living Things
Life Comes From Life
Louis Pasteur’s carefully controlled experiment demonstrated that bacteria arise only from existing bacteria.
- What Is Life?
Living Things
Look at the section headings and visuals to see what this section is about. Then write what you already know about living things in a graphic organizer like the one below. As you read, write what you learn.
What You Know
What You Learned
1. Living things grow.2. Living things are made of cells.
1. Unicellular organisms are composed of only one cell.2. The cells of living things are composed of chemicals.3. The cells of organisms use energy to do things they must do.
- What Is Life?
Using Prior Knowledge
Living Things
End of Section:What Is Life?
Living Things - Classifying Organisms
Levels of Classification
As you move down the levels of classification, the number of organisms decreases. The organisms at lower levels share more characteristics with each other.
Living Things
Aristotle and Classification
Many hundreds of years before Linnaeus, a Greek scholar named Aristotle developed a classification system for animals. Aristotle first divided animals into those he considered to have blood and those he did not. This graph shows Aristotle’s classification system for “animals with blood.”
- Classifying Organisms
Living Things
Aristotle and Classification
3
Reading Graphs:
Into how many groups were these animals classified?
- Classifying Organisms
Living Things
Aristotle and Classification
Animals that fly
Interpreting Data:
Which group made up the largest percentage of animals?
- Classifying Organisms
Living Things
Aristotle and Classification
78%
Calculating:
What percentage of these animals either fly or swim?
- Classifying Organisms
Living Things
Aristotle and Classification
Cow- animals that walk, run, or crawl; whale- animals that swim.
Inferring:
In Aristotle’s classification, where would a cow be classified? A whale?
- Classifying Organisms
Living Things
Aristotle and Classification
Possible answer: This system includes only three categories, so it may not be very useful today. It also does not match that of modern scientists, who use characteristics other than movement to classify animals. For example, frogs and lions belong to very different groups.
Predicting:
Would Aristotle’s classification system be used today? Explain.
- Classifying Organisms
Living Things
Taxonomic Keys
Taxonomic keys are useful tools for determining the identity of organisms.
- Classifying Organisms
Living Things
eats eats eats
Evolution and ClassificationSpecies with similar evolutionary histories are classified more closely together. These Galapagos finches may have arisen from a single species and changed gradually over time to become three separate species. Notice the differences in their appearance, especially their beaks.
- Classifying Organisms
Living Things
Question Answer
Asking QuestionsBefore you read, preview the red headings. In a graphic organizer like the one below, ask a what, why, or how question for each heading. As you read, write the answers to your questions.
Why do scientists classify? Scientists classify because they want to organize living things into groups so they are easier to study.
What system did Linnaeus use to name organisms?
He used a system called binomial nomenclature.
What are the levels of classification? Domain, kingdom, phylum, class, order, family, genus, species
- Classifying Organisms
Living Things
More on Classifying Living Things
Click the PHSchool.com button for an activity about classifying living things.
- Classifying Organisms
Living Things
End of Section:Classifying Organisms
Living Things - Domains and Kingdoms
Three Domains of Life
In the three-domain system of classifications, all known organisms belong to one of three domains–Bacteria, Archaea, or Eukarya.
Living Things
As you read, compare and contrast the characteristics of organisms in domains Bacteria, Archaea, and Eukarya by completing a table like the one below.
- Domains and Kingdoms
Characteristics of Organisms
Domain or Kingdom Cell Type and Number Able to Make Food?
Bacteria
Archaea
Eukarya:Protists
Fungi
Plants
Animals
Prokaryotes; unicellular Some are able to make food
Some are able to make food
Some are able to make food
No
Yes
No
Prokaryotes; unicellular
Eukaryotes; unicellular or multicellularEukaryotes; unicellular or multicellularEukaryotes; multicellular
Eukaryotes; multicellular
Comparing and Contrasting
Living Things
Links on Kingdoms
Click the SciLinks button for links on kingdoms.
- Domains and Kingdoms
Living Things
End of Section:Domains and
Kingdoms
Living Things - The Origin of Life
The Atmosphere of Early Earth
On ancient Earth, water vapor, carbon dioxide, and methane were probably the most abundant gases in the atmosphere. There were frequent volcanic eruptions, earthquakes, and violent storms.
Living Things
As you read, identify the evidence that supports scientists’ hypothesis of how life arose on Earth. Write the evidence in a graphic organizer like the one below.
Origin of life
Fossil evidence of achaea-like organisms
Fossils dated to be between 3.4 and 3.5
billion years old.
- The Origin of Life
Hypothesis
Evidence
Identifying Supporting Evidence
Living Things
Links on the Origin of Life
Click the SciLinks button for links on the origin of life.
- The Origin of Life
Living Things
End of Section:The Origin of Life
Living Things
Graphic Organizer
Water Living space
Autotrophs
Heterotrophs
Food & water
need
made by
eaten by
to provide
Food
Living Things
Homeostasis
Shelter
Living Things
End of Section:Graphic Organizer