1. The Endomembrane System
Rough ER
Transport
vesicle from ER
Golgi
apparatus
Secretory
vesicle from Golgi
Secretory
protein
Vacuole
Lysosome
Plasma membrane

2. The Endoplasmic Reticulum
Produces an enormous variety of molecules
Is composed of smooth and rough ER
Nuclear
envelope
Ribosomes
Rough ER
Smooth ER

3. The Endoplasmic Reticulum
After the rough ER synthesizes a molecule it packages the molecule into transport vesicles 4
Transport vesicle
buds off
Secretory
protein inside
transport
vesicle
Ribosome 3
Protein 1
Rough ER 2
Polypeptide

4. The Golgi Apparatus Works in partnership with the ER
Refines, stores, and distributes the products of cells
Transport
vesicle
from ER
“Receiving” side of
Golgi apparatus
Golgi apparatus
New vesicle forming
Transport vesicle
from the Golgi
“Shipping” side of
Golgi apparatus
Plasma membrane

5. Lysosomes A lysosome is a membrane-enclosed sac
It contains digestive enzymes
The enzymes break down macromolecules
They break down damaged organelles
Lysosome
Digestion
Damaged
organelle
(b) Lysosome breaking down damaged organelle

6. Vacuoles
Vacuoles are membranous sacs

7. Cellular energy conversion
Mitochondria are the sites of cellular respiration, which involves the production of ATP from food molecules
Outer
membrane
Inner
membrane
Cristae
Matrix
Space between
membranes
Figure 4.18

8. Cytoskeleton
● Provides mechanical support to the cell and maintain its shape 8

9. The Cytoskeleton *microtubules *microfilaments (actin filaments)
*intermediate filaments

10. Microfilaments

11. Microtubules
*centrosome *centrioles

12. Cilia and Flagella Cilia and flagella are motile appendages
Flagella propel the cell in a whiplike motion
Cilia move in a coordinated back-and-forth motion

13. Cilia and Flagella
“9 + 2”
basal body

14. The Cytoskeleton
dynein – motor molecules

15. Plant Cells Not in animal cells Cytoskeleton Mitochondrion Central
vacuole
Nucleus
Cell wall
Rough endoplamsic reticulum (ER)
Chloroplast
Ribosomes
Plasma
membrane
Smooth
endoplasmic
reticulum (ER)
Plasmodesmata
Golgi apparatus

16. Plant Cells Plant cells are encased by cell walls
Walls of two adjacent
plant cells
Vacuole
Plasmodesmata
(channels between cells)

17. Chloroplasts
Inner and outer
membranes of
envelope
Chloroplasts are the sites of photosynthesis, the conversion of light energy to chemical energy
Space between
membranes
Granum
Stroma (fluid in
chloroplast)

18. Origin of Eukaryotes