The document defines cell modification as specialized adaptations that help cells function effectively after division, categorizing them into three types: apical, basal, and lateral modifications. It describes specific examples including cilia, flagella, microvilli, and various cell junctions such as tight and gap junctions, detailing their functions and structures. Additionally, the document explains the extracellular matrix and its components in relation to cell modifications.

1. C h a p t e r 4
Cell Modification

2. Learning Objectives:
 Define cell modification
 enumerate and describe the three types of cell
modification
 characterize apical, basal and lateral cell
modifications
 give examples of apical, basal and lateral cell
modifications

3. Overview:
 Definition of Cell modification
 Three types of Cell Modification
 Examples of Apical, Basal and Lateral
Cell Modification
 Functions of the different Cell Modification

4. What is Cell Modification?
 Are specialized or modifications re-acquired by
the cell after cell division that helps the cell in
different beneficial ways

5. Cell
Modification
Apical
Cilia
Flagella
Microvilli
Pseudopods
C
e
l
l
w
a
l
l
ECM
Glycoprotein Collagen
Basal Hemidesmosomes
Lateral
Tight Junctions
Adhering Junctions
Gap Junctions

6. basement membrane
A Three types of cell junctions in animal tissues.
gap junctions
adhering junctions
tight junctions
free surface of epithelial tissue
plasmodesma
ER
cytoplasm
plasma
membrane
cell wall
B Plasmodesmata are channels
that connect the cytoplasm and ER
of adjacent plant cells.

7. Apical Modification
 Cell modification found on
the apical surface of the
cell
basement membrane
gap junctions
adhering junctions
tight junctions
free surface of epithelial tissue

8. Apical Modification
Cilia and Flagella
Cilia are usually short,
hair-like structures that
move in waves
Flagella are long whiplike
structures
Formed from
microtubules

9. Apical Modification
Cilia Flagellum

10. Apical Modification
Villi and Microvilli
 Villi are finger-like projections
that arise from the epithelial
layer in some organs. They
help to increase surface area
allowing for faster and more
efficient adsorption
 Microvilli are smaller projections
that arise from the cell's
surface that also increase
surface area allowing faster
and more efficient absorption

12. Apical Modification
Pseudopods
Temporary, irregular
lobes formed by
amoebas and some
other eukaryotic cells
Bulge outward to
move the cell or
engulf prey

13. Apical Modification
Extra Cellular Matrix (ECM)
Compound secreted by the cell on its apical
surface
Cell wall is the extracellular structure in plant
cells that distinguishes them from animal cells
Glycoprotein is the main ingredient of ECM in
animal cells

14. Apical Modification

15. Basal Modification
 Cell modification found on
the basal surface of the
cell
basement membrane
gap junctions
adhering junctions
tight junctions
free surface of epithelial tissue

16. Basal Modification
Desmosomes/Hemidesmosomes
 Anchoring junction on the
basal surface of the cell
 Rivet-like links between
cytoskeleton and extracellular
matrix components such as
the basal lamina that underlie
epithelia
 Primarily composed of keratin,
integrins and cadherins

17. Basal Modification

18. Lateral Modification
 Cell modification found
on the basal surface
of the cell

19. Lateral Modification
Tight Junction
Act as barriers that
regulate the movement
of water and solutes
between epithelial layers
Prevent leakage of ECF

20. Lateral Modification
Adhering Junction
Anchoring junction on the
lateral surface of the cell
Very similar to the
anchoring junction of the
basal surface of the cell
Fasten cells to one
another basement membrane
Three types of cell junctions in animal tissues.
gap junctions
adhering junctions
tight junctions
free surface of epithelial tissue

21. Lateral Modification
Gap Junction
Also known as
communicating junctions
Closable channels that
connect the cytoplasm of
adjoining animal cells
Presence of connexon that
allow direct exchange of
chemicals between the
cytoplasm of two cells basement membrane
Three types of cell junctions in animal tissues.
gap junctions
adhering junctions
tight junctions
free surface of epithelial tissue

22. Assignment
Visit the link:
http://www.diffen.com/difference/Eukaryotic_Cell_v
s_Prokaryotic_Cell