Download Cell Structure

CELLS
Structure and Function
Cell = smallest unit of life
Two Major Cell Types
Cell Type
Prokaryotic
Eukaryotic
Example
Bacteria
Protists
Fungi
Plants
Animals
Prokaryotic Cell
Eukaryotic Cell
(protist, animal)
Eukaryotic Cell
(plant)
Differences Between Cell Types
Prokaryotic Cell
Single circular
chromosome
Eukaryotic Cell
Multiple linear
chromosomes
Chromosome found Chromosomes found
in a cytoplasmic
in a membraneregion called the
bound nucleus.
nucleoid.
No internal
membranes
Some infolded
plasma membrane
Extensive network of
internal membranes
Common Components
and Cellular Organization
• Plasma Membrane
– boundary surrounding the cell
• Genetic material: DNA
– located in a membrane-bound nucleus
for eukaryotic cells
• Cytoplasm
– Semi-fluid matrix containing enzymes
and organelles
(enzyme = biological catalyst)
• Cytoskeleton
– network of filaments and tubules in cytoplasm
that maintains cell shape, allows movement
Features of
Prokaryotic Cells
All prokaryotic cells contain
Structure
Plasma
Membrane
Nucleoid
Cytoplasm
Function
Regulates flow of
substances into and out
of cell
Cytoplasmic region
containing genetic
material
Cytosol: fluid
Ribosomes
Enzymes
Features of
Prokaryotic Cells
Other possible prokaryotic structures
Structure
Cell Wall
Capsule
Infolded Plasma
Membranes
Function
Supports cell
Maintains shape
Protects from drying
Protects against
white blood cells
Metabolism
Cell division
Features of
Prokaryotic Cells
Other possible prokaryotic structures
Structure
Bacterial
Flagellum
Plasmid
Function
Movement
Small circular DNA
Replicates
independently
Applying Your Knowledge
1.
2.
3.
4.
5.
Cell Wall
Flagellum
Capsule
Plasmid
Nucleoid
In bacterial cells
• where is the genetic material located?
• which one is used for movement?
• which one provides structural support
for the cell?
Functions of Eukaryotic Cell Features
Structure
Function(s)
1. Regulates passage of
Plasma
materials into and out of cell
Membrane
2. Cell-Cell Recognition
Functions of Eukaryotic Cell Features
Structure
Cell Wall
(protists,
fungi, plants)
Function(s)
1. Controls cell shape,
protects, supports
Functions of Eukaryotic Cell Features
Structure
Nucleus
Function(s)
1. Carrier of genetic material
DNA + protein = chromatin
2. Governs cell activities
3. Directs cell reproduction
4. Surrounded by Membrane
= nuclear envelope
5. Contains nucleolus—
produces ribosomes
which synthesize proteins
Functions of
Eukaryotic
Cell Features
Structure
Rough
Endoplasmic
Reticulum (RER)
Smooth
Endoplasmic
Reticulum (SER)
SER
RER
Function(s)
1. Associated ribosomes produce
proteins
2. Prepares proteins for export
1. Lipid Synthesis
2. Drug detoxification
3. Transport of proteins from RER
Functions of Eukaryotic
Cell Features
Structure
Function(s)
Golgi
Apparatus
Collects, modifies, packages and
distributes proteins and lipids from ER
Functions of
Eukaryotic
Cell Features
Structure
Lysosome
Function(s)
Contains digestive enzymes
to digest food in protists or
destroy aging organelles
Endomembrane System
Rough
Endoplasmic
Reticulum
Smooth
Endoplasmic
Reticulum
Vesicle
Golgi
Apparatus
Vesicle
Lysosome
Vesicle
Plasma
Membrane
Functions of
Eukaryotic
Cell Features
Structure
Peroxisome
Function
Removes harmful oxidants
from cells
Functions of
Eukaryotic Cell
Features
Structure
Mitochondrion
Function
Captures energy from
organic molecules,
producing ATP
Functions of
Eukaryotic Cell
Features
Structure
Function
Chloroplast
Photosynthesis: Uses light
(protists, plants) energy to produce organic
molecules
Functions
of Eukaryotic
Cell Features
Structure
Function(s)
Cytoskeleton
1. Maintains cell shape
2. Anchors organelles and proteins
3. Allows for organelle movement
and cellular movement in some
cell types
Functions of
Eukaryotic Cell
Features
Structure
Function
Centriole
Gives rise to basal bodies that
produce cilia or flagella
Functions of
Eukaryotic Cell
Features
Structure Function(s)
Vacuole
1. Central vacuole (plants) stores
waste, maintains turgidity.
2. Contractile vacuole (protists)
maintains water balance.
3. Food vacuole (protists) fuses
with lysosome for digestion.
Functions of Eukaryotic
Cell Features
Structure
Cilia and
Flagella
Function(s)
1. Move substances across
cell surface in lungs,
fallopian tubes
2. Cell movement in sperm,
protists
Applying Your Knowledge
1.
2.
3.
4.
5.
Cilium
Rough ER
Golgi apparatus
Smooth ER
Lysosome
A. Which organelle produces proteins that
will be exported from the cell?
B. Which organelle contains digestive
enzymes?
C. Which site acts as a protein packaging
and distribution center?
Thought Questions
1. What are similarities for
a. eukaryotic and prokaryotic cells?
b. animal and plant cells?
2. What are differences between
a. eukaryotic and prokaryotic cells?
b. animal and plant cells?
Analogy
If the cell were a factory
the ____________________ would be
(name a cell component)
a _____________________________.
(name a part of a factory)
Part of Cell
Part of Factory
Capsule
Security Gate
Cell Wall
Outer Fence around the factory
Chloroplast
Solar Panel
Cytoskeleton
Moving Belt where items are inspected
Steel Support, Interior Walls
Cilia/Flagella
Conveyor Belt, Elevator/Escalator
Enzyme
Worker; Assemblage Machinery
Golgi Complex
Distribution/Packaging Department
Mailroom
Mitochondrion
Generator, Engine Room, Power Source
Nucleoid
Storage of pre-production material
Nucleus
Supervisor’s Office, Boss
Corporate Office, Central Operations
Plasma Membrane
Loading/Unloading Dock, Inner Wall, Door
Ribosomes
Assembly Line Track
RER
Production Line
SER
Shipping Dock
Cellular Interactions
 Signal Transduction: passing a signal
from the cell surface to the interior
 First messenger binds to
Cell Surface Receptor
 Receptor signals nearby
Regulator Protein
 Regulator activates
nearby enzyme
 Enzyme catalyzes formation
of Second Messenger
 Second Messenger initiates
Cellular Response
Cellular Interactions
 Cell Adhesion: joining of cells
controlled by proteins called
Cellular Adhesion Molecules
(CAMS)
important in
 Inflammatory Response
 Placenta Formation
 Learning and Memory
Lack of cell adhesion is
implicated in cancer
and arthritis.