Unit 3, Lesson 3.4 - Prokaryotes vs. Eukaryotes Lesson Outline: 1. Major Comparisons of Prokaryotic and Eukaryotic Cells 2. The Prokaryotic Cell

1. Prokaryotes vs.
Eukaryotes
UNIT THREE, LESSON 3.4
BY MARGIELENE D. JUDAN

2. LESSON OUTLINE
Major Comparisons of Prokaryotic and Eukaryotic Cells
The Prokaryotic Cell

3. All cells are
composed of 3
major parts:
1. External
coverings
(cell
membrane or
wall)
2. Cytoplasm
3. Nucleus

4. External Covering

5. Prokaryotes’ coverings:
1. capsule
2. Cell wall
3. Cell membrane

6. Eukaryotes’ coverings:
1. Either cell wall or cell membrane.
Plant cells have both.
Animals cells have cell membrane only.

7. Cytoplasm

8. As mentioned in the
previous lesson,
cytoplasm is the
semisolid, semiliquid
substance inside the
cell which includes
the organelles.

9. Cytoplasm is present
in both prokaryotes
and eukaryotes.
Cytoplasm + nucleus
= protoplasm

10. Cytoplasm is present
in both prokaryotes
and eukaryotes.
Cytoplasm + nucleus
= protoplasm

11. Prokaryotes –
pro means
before; karyon
means nucleus

12. Eukaryotes –
eu means true;
karyon means
nucleus

13. Nucleus

14. The nucleus
contains the
DNA, which
contains all the
codes necessary
for life.

15. Prokaryotes have no
true nucleus
The DNA is
suspended in a dense
part of cytoplasm
called nucleoid
region.

16. Eukaryotes have
nucleus with a
double membrane.

17. According to
evolutionary
theory, the complex
nucleus of
eukaryotes
originated from the
nucleoid region of
prokaryotes.

18. That’s why
prokaryote
means “before
nucleus
(referring to
eukaryotes)”.

19. Major Comparisons
(Summary)

20. Major Cellular
Parts
Prokaryotic Cell Eukaryotic Cells
(Animals)
Eukaryotic Cells
(Plants)
Covering
• Capsule 
• Cell wall  
• Plasma
membrane
  
Cytoplasm   
Nucleus  
Nucleoid region 

21. Both pro- and
eukaryotes
perform the same
biological
functions. The
only difference is
their structure.

22. Eukaryotes have
a more complex
structure and
organelles.

23. The Prokaryotic Cell
(unicellular or w/ one cell)

25. The Prokaryotic Cell
1. Coverings
2. Cytoplasm
3. Nucleus

26. 1. Coverings
Capsule
Cell wall
Cell or plasma
membrane

27. 1. Coverings
Layer Location Composition Function
Capsule Outermost Glycocalyx (a sticky
chemical/carbohydrat
e)
Attaches prokaryotic
cell to surface;
protection and
support
Cell wall Between capsule and
plasma membrane
Peptidoglycan Promotes additional
protection and
support
Plasma membrane innermost Phospholipid bilayer Protection and
support; passageway
of materials exiting
and entering the cell

28. Also, locomotive
organelles (ex.
flagella) are also
attached to the
plasma
membrane to
enable the
organism to
move.

30. The flagella
enables
movement as it
propels in a
circular way.

31. Another, the fimbriae, are appendages that function more
for adhesion (attachment to a surface) and lesser for
movement. It is also used in attaching the zygote in the
mother’s womb. Pili are longer than fimbriae.

32. 2. Cytoplasm
The semisolid/
semiliquid/ gel-like
substance that hold the
internal parts
(organelles)
They have inclusions,
which store organic
molecules and supply it
if needed.

33. 3. Nucleoid region
The dense region in
cytoplasm that
contains the DNA.

34. 3. Nucleoid region
Their DNA is called a
plasmid. It is circular
or loop in shape, not
double helix.
Loop or circular DNA (prokaryotes only)
Double helix DNA
(eukaryotes only)

35. 3. Nucleoid region
Plasmids are
important especially
when danger arises.
Loop or circular DNA (prokaryotes only)
Double helix DNA
(eukaryotes only)

36. 3. Nucleoid region
When danger
happens, a prokaryote
transfers the plasmid
to another
prokaryote. The
process is called
conjugation. The pili
serve as a spiked tube
for transfer.

37. Pili are used like a
needle to transfer the
plasmid.

39. Short quiz tomorrow: (10 items)
Study only Table 2.1 (p.103) and Table 2.2 (p.104)
After the quiz, each group will perform the “Cell Theory
Song”.
You may spend the remaining time to practice your
performance tomorrow.

40. Sources:
Science Links 7