Biology

1. Introduction To Cells

2. 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

3. 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?)

4. Cell Similarities
 All
 Have cell membrane
 Contain hereditary material (DNA)
 Have Cytoplasm and Ribosomes
 Are small in size
 Most cannot be seen with naked eye
 Ostrich egg

5. 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

6. 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)

7. Prokaryotic Cells: Bacteria
 Either classified as eubacteria or
archaea.
 Eubacteria: commonly found
 Archaea: Live in extreme environments

8. 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

9. Prokaryotic Cells: Bacteria
“The Bad”
 Food Spoilage
 Can cause disease in plants and
animals
 Produce Toxins

10. 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

11. Prokaryotic Cells: Bacteria
 Ways to prevent disease:
 Wash hands!!!
 Cook food thoroughly.
 Keep foods cold.(slows metabolism)
 Antibiotics

12. 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

14. Cell Movement
 Flagella: tail-like projections
 Pseudopod: false-foot
 Cilia: finger-like projections (some
non-motile)