Transcript Chapter 2 Notes

Classification and Cells
2.2-2.4
Section 2.2
• Currently 1.8 million species of living
organisms
• Classifying 15,000/year new species
• Many species have gone extinct
• Scientists believe 10-100 million
species
• Look at Figure 7 page 43
• What characteristics may have been
used to group these beetles?
Why do Scientists Classify?
• Classification
• Process of grouping
things based on
similarities
• Taxonomy
• Study of how living
things are classified
• Also involves naming
organisms
Naming System of Linnaeus
• Carolus Linnaeus a Swedish Naturalist
in 1750’s
• Classified based on observable
features
• Binomial Nomenclature
• Written in italics and Latin, first
letter capitalized
• Two names
• Genus – similar, closely related species
• Species – group of organisms,
physically similar that can mate
Levels of Classification
• Three Domains:
• 1. Eukarya – membrane bound
nuclei
– Protists, Fungi, Plants, Animals
• 2. Archaea –
• “ancient”
• 3. Bacteria – Prokaryotes – cells
without a nucleus
6
Kingdoms
Prokaryotes - microscopic no distinct
nuclei now divided into 2 kingdoms
1. Archaebacteria - anaerobic (deep)
2. Eubacteria - everywhere 10,000 species
3. Protista – “odds and ends” eukaryote
lacks a complex organ system and lives in
moist environments
4. Fungi- multicellular, decomposers,
mushrooms, molds, mildew
5. Plants - multicellular oxygen producers
6. Animals - Multicellular consumers,
diverse, heterotrophs
Discovering Cells 2.3
• Cell –
• basic unit of structure
and function of living things
Microscope
• Magnifies small objects
• Invention allowed people to see cells
• Construct a flowchart stating
showing how Hooke, Leeuwenhoek,
Schleiden, Schwann and Virchow
contributed to the scientific
discovery of cells
Cell Theory
• 1. All living things are
composed of cells
• 2. Cells are the basic unit of
structure and function in
living things
• 3. All cells are produced from
other cells.
Light and Electron Microscopes
• Compound Microscope –
• using more than one lens
– Multiply lenses together
• Resolution – how sharp it looks
• Electron Microscope –
• Use a beam of electrons
instead of light to produce a
magnified image
• 1. What does the red bar represent?
What does the blue bar represent?
• 2. What percentage of the mammalian
cell is made up of water?
• 3. Compare that to the water in the
bacterial cell.
• 4. What kind of compound, proteins or
nucleic acids is found in larger
concentrations in the mammalian cell?
• 5. How do the bacterial and mammalian
cell compare?