Transcript Cell Structures and Functions

Components of the Cell System
To know prokaryotic and eukaryotic cell structures and their functions
How does the cell work as a system responsible for maintaining life?
Prokaryotes vs.
Eukaryotes
Cell Membrane
Cell Wall
Nucleus
Cytoplasm
Mitochondria
Chloroplast
Components of the
Cell System
Structures and their Functions
Two Basic Types of Cells form a
great diversity
Prokaryotes vs. Eukaryotes
Prokaryotic Cells - a simple but
effective compartment


Eubacteria and
Archaea
Cell membrane,
cytoplasm,
ribosomes, and
DNA
Eukaryotic Cells - A compartment
full of compartments
 Animals,
plants,
fungi, and
protists
 Contain a
nucleus and
many organelles
1. Cell Membrane




Outside boundary of cell
Double (“bi”) layer of
phospholipid molecules
Proteins embedded within;
have different functions
Protects cell and regulates
what enters and exits
2. Cell Wall




Plants, some fungi,
some bacteria, some
protists have this
Outside of membrane
Provides structure
Made of carbohydrates
(mainly cellulose, which
we know as fiber)
3. Nucleus


Pores in the nuclear
membrane control
flow of materials in
and out.
Holds DNA and
controls the cells
activities.
Transmission EM of Nucleus.
3.5 Nucleolus


Region within the
nucleus where
ribosomes are
formed
Ribosomes?… so
ALSO where
proteins are also
formed!
4. Cytoplasm




Present in all cells
Jelly-like mixture of water,
proteins, salt and
carbohydrates.
Organelles are embedded
in cytoplasm
Can be used
interchangeably with
“hyaloplasm”
The Organelles
Smaller, specialized
compartments within a
cell
5. Mitochondria


Where energy stored in
food is converted for use
in the cell
Number of mitochondria
in a cell depends on the
purpose of the cell


Muscle cells 
Skin cells 
6. Chloroplasts


Chlorophyll - green
pigment that allows for
photosynthesis
Flattened sacs within
“Thylakoids”, where
photosynthesis occurs
7. Ribosomes: Not compartments!
No membrane; they
are composed of two
subunits
 Proteins that make
proteins
 The most abundant
of all cell parts

8. Endoplasmic Reticulum


Like a highway where
molecules move from
one part of the cell to
another
Two types: rough and
smooth
8a. Rough Endoplasmic
Reticulum
 Studded
with
ribosomes!
 Processes
proteins to export
from the cell
8b. Smooth Endoplasmic
Reticulum
 No
ribosomes!
 Makes lipids
(fats and
steroids)
 Detoxification in
liver cells
9. Golgi Bodies/Apparatus



System of flattened
sacs called cisternae
Works with the RER to
modify, package and
release proteins
Spawns vesicles to
transport materials to
the cell membrane
10. Vacuoles
In plant cells: large
and used for water +
nutrient storage
 In animal cells: small
and numerous and
contain a variety of
substances

11. Lysosomes



Contain chemicals for
digesting waste, toxins,
or useless organelles
Formed from Golgi
Common in animal and
fungus cells
How do we
know all this?
Cell Theory- 1839
The microscope opened a world of discovery of life
never seen before. By 1839, scientists Matthias
Schleiden, Theodor Schwann and Rudolf Virchow
concluded the following as the….
Cell Theory
1. All living things are made of cells.
2. Cells are the basic unit of structure
and function in living things.
3. All cells come from other cells.