Transcript Intro to Cells

Introduction To Cells
History & Definition
 First cells seen where cork cells in 1665
by Robert Hooke.
 A cell is the smallest unit that can still
carry on all life processes.
 Ex. Red blood cells, nerve cells
Cell Theory
 All organisms are composed of one or
more living cells
 The cell is the basic unit of life in all
living things.
 All cells come from existing cells.
(chicken or the egg?)
Cell Similarities
 All
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Have cell membrane
Contain hereditary material (DNA)
Have Cytoplasm and Ribosomes
Are small in size
 Most cannot be seen with naked eye
2 Main Types of Cells
 Prokaryotic
Include bacteria
Do NOT have a nucleus
Have long circular DNA
No membrane bound
organelles
 Contain ribosomes to
make proteins.
 rod shaped, spherical, and
spiral
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Prokaryotic Cells: Bacteria
 Reproduction: Usually Asexual
 Binary Fission: an organism duplicates its DNA
and then divides into two parts, with each new
organism receiving one copy of DNA.
 Conjugation: Exchange of DNA between bacteria
(not Asexual)
Prokaryotic Cells: Bacteria
 Either classified as eubacteria or
archaea.
 Eubacteria: commonly found
 Archaea: Live in extreme environments
Prokaryotic Cells: Bacteria
“The Good”
 Bioremediation: organisms are added to
water to convert toxic pollutants, such as
oil, into harmless substances.
 Food Production: Butter, Cheese, Yogurt,
Sauerkraut, Beer, Pickles, Olives,
Chocolate, Coffee, Soy sauce, meats,
etc.
 Decompose dead organisms
 Digesting food
Prokaryotic Cells: Bacteria
“The Bad”
 Food Spoilage
 Can cause disease in plants and
animals
 Produce Toxins
Prokaryotic Cells: Bacteria
“The Ugly”
 Must be dealt with every day.
 People die each year from infections.
 Bubonic Plague:
 Killed 2 out of 3 patients in 2-6 days without
treatment
 Yersina pestis
 Anthrax
Prokaryotic Cells: Bacteria
 Ways to prevent disease:
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Wash hands!!!
Cook food thoroughly.
Keep foods cold.(slows metabolism)
Antibiotics
2 Main Types of Cells
 Eukaryotic (YOU!)
 More complex & larger
than proK
 Have membrane bound
organelles
 Has a nucleus
 Has more DNA than proK
 DNA is linear
 Animal, plant, fungi
 NOT BACTERIA
Cell Movement
 Flagella: tail-like projections
 Pseudopod: false-foot
 Cilia: finger-like projections (some
non-motile)