Transcript Cells Part 1

Cells I
Cells Part I
Living Things:
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Highly organized
Convert energy
for their own use
Control internal
environment
(Homeostasis)
Have adaptations
Respond to stimuli
Grow
Reproduce
Have emergent properties
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Characteristics of Living Things
Discovery of Cells 17th Century
Robert Hooke
observed cork in a
microscope.
Anton van Leeuwenhoek
described “animalcules” he
found in tooth plaque.
Cell Theory
1.
The cell is the smallest
unit of life.
2.
All organisms are made
from one or more cells.
3.
Cells arise from
pre-existing cells.
Schleiden & Schwann
Different types of microscopes are
used to study cells
Stereo Microscope
1-celled organisms
Light Microscope
Most cells
Electron Microscope
Cells  small molecules
Scanning Electron Microscope
3-D images
Two Categories of Cells
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Prokaryotes
“Before” nucleus
Simple structure
Bacteria
Archaebacteria
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Eukaryotes
True nucleus holds DNA
Many cell parts with
special functions
One cell or multicellular
organisms
Plants! Animals!
People!
Hierarchy of
organization
in complex
organisms
Tissues and
organs have
specialized
functions
Cells have structures specialized for:
Providing a barrier between cell &
environment
 Storing information for building &
maintaining cell(software)
 Manufacturing cell parts & machinery
 Maintenance
 Energy processing
 Support, movement & communication
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All cells have:
Cell membrane
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Surrounds, contains, protects
 Cytoplasm
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“Cell gel” fills interior of cell
 Ribosomes
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Help make proteins for cells
 DNA
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Coded instructions for cell
(software)
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Stop here.
 Explore cell parts using GSLC website or
Cells Alive
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Prokaryotic cells may also have:
Cell wall – surrounds cell membrane;
protects, maintains shape
 Capsule – additional protection;
“glue”
 Prokaryotic Flagellum – movement
 Pili – attach bacteria to surfaces
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Escherichia coli (E. coli):
a simple bacterial cell
Helicobacter (causes ulcers)