Transcript A Tour of the Cell

TEM - interior
SEM - surface
Animal Cell
Plant Cell
Endomembrane System
Endoplasmic
Reticulum
Often
referred to as ER.
Makes up to 1/2 of the total
membrane in cells.
Often continuous with the
nuclear membrane.
Structure of ER
Folded
sheets or tubes of
membranes.
Very “fluid” in structure with
the membranes constantly
changing size and shape.
Types of ER
Smooth
ER: no ribosomes.
Used for lipid synthesis,
carbohydrate storage,
detoxification of poisons.
Rough ER: with ribosomes.
Makes secretory proteins.
Function of Golgi
Bodies
Processing
- modification of
ER products.
Distribution - packaging of
ER products for transport.
Golgi Vesicles
Small
sacs of membranes
that bud off the Golgi Body.
Transportation vehicle for the
modified ER products.
Lysosome Function
Breakdown
and degradation
of cellular materials.
Contains enzymes for fats,
proteins, polysaccharides,
and nucleic acids.
Over 40 types known.
Lysosomes
Important
in cell death.
Missing enzymes may cause
various genetic enzyme
diseases.
Examples: Tay-Sachs,
Pompe’s Disease
Vacuoles
Structure
- single membrane,
usually larger than the Golgi
vesicles.
Function - depends on the
organism.
Function
Water
regulation.
Storage of ions.
Storage of hydrophilic
pigments.
(e.g. red and blues in flower
petals).
Function: Plant vacuole
Used
to enlarge cells and
create turgor pressure.
Enzymes (various types).
Store toxins.
Coloration.
Enzymes in a
crystal
Mitochondria
Structure:
2 membranes.
The inner membrane has
more surface area than the
outer membrane.
Matrix: inner space.
Intermembrane space: area
between the membranes.
Inner Membrane
Folded
into cristae.
Amount of folding depends
on the level of cell activity.
Contains many enzymes.
ATP generated here.
Function
Cell
Respiration - the release
of energy from food.
Major location of ATP
generation.
“Powerhouse” of the cell.
Chloroplasts
Structure
- two outer
membranes.
Complex internal membrane.
Fluid-like stroma is around
the internal membranes.
Inner or Thylakoid
Membranes
Arranged
into flattened sacs
called thylakoids.
Some regions stacked into
layers called grana.
Contain the green pigment
chlorophyll.
Function
Photosynthesis
- the use of
light energy to make food.
Plastids
Group
of plant organelles.
Structure - single membrane.
Function - store various
materials.
Examples
Amyloplasts/
Leucoplasts -
store starch.
Chromoplasts - store
hydrophobic plant pigments
such as carotene.
Cytoskeleton
Network
of rods and
filaments in the cytoplasm.
Functions
Cell
structure and shape.
Cell movement.
Cell division - helps build cell
walls and move the
chromosomes apart.
Cytoskeleton
Very
dynamic; changing in
composition and shape
frequently.
Cell is not just a "bag" of
cytoplasm within a cell
membrane.
Cell Wall
Nonliving
jacket that
surrounds some cells.
Found in:
Plants
Prokaryotes
Fungi
Some
Protists
Plant Cell Walls
All
plant cells have a Primary
Cell Wall.
Some cells will develop a
Secondary Cell Wall.
Cell Walls
May
be made of other types
of polysaccharides and/or
silica.
Function as the cell's
exoskeleton for support and
protection.