Cytoplasm and
Cytoskeleton
By: Tim Yacoub and Lizette
Magdaleno
Cytoskeleton Overview
 Cytoskeleton
is a “network of fibers that
extend[s] throughout the
cytoplasm,”(113).
 It’s three structures: microtubules,
microfilaments, and intermediate
filaments
 It helps with the organization of activities,
cell mobility, and structure of the cell
Cytoskeleton: Microtubules
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In all eukaryotic cells, Shape: hallow tubes
Made from protein called tubulin by
centrioles
Help shape and support the cell,
Compression-resistant, function as roads for
mobile organelles to move along.
Aid in chromosome separation in cell division.
Special arrangement of microtubules form
flagella and cilia.
Cytoskeleton: Microfilaments
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In all eukaryotic cells, Shape: thin solid rods
Made from a globular protein: Actin, (twisted
double chain of actin subunits).
Functions as a tension bearer, networks inside
the plasma membrane to support cell shape,
this layer is called a cortex.
Well known for its aid in cell movement, actin,
along with Myosin interact, for example, to
contract muscle cells
Cytoskeleton: Intermediate
Filaments
 Coiled
cables, larger than microfilaments
but smaller than microtubules
 Made of several proteins similar to keratins
 Only in some animal cells , bears tension
(like microfilaments)
 More of a permanent structure within the
cytoskeleton
 Reinforces shape of cell, and anchors
certain organelles within the cytoplasm
Cytoplasm Overview
 Cytoplasm
is “the contents of the cell
bounded by the plasma membrane, in
eukaryotes, the portion exclusive of the
nucleus.” (G-9)
Cytoplasm: Structure
 It
is the Fluid where the cellular organelles
are suspended.
 It fills up all the spaces in the cell that are
not being filled by the organelles
 3 Residents of Cytoplasm:
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1.Cytosol
2.Organelles
3.Cytoplasmic Inclusions
Cytoplasm: Characteristics
 Fluid
substance that fills the space
between the cell membrane and cellular
organelles
 High percentage of water
 It is colloidal
 It contains proteins
 90% water and 10% organic and
inorganic compounds
Cytoplasm: Zones
 Plasmogel-
peripheral zone of cytoplasm
that is thick and jelly- like
 Plasmosol-
zone is thin and liquefied
Cytoplasm: Function
 Site
of many biochemical reactions
 Place where cell expands and grows
 Provides a medium for organelles to
remain suspended
 Aids in movement of different cellular
elements
 Break down macromolecules
 Transport of genetic material