Organelles in cells include the nucleus, which contains DNA, nucleolus, which produces ribosomes, and ribosomes, which produce proteins. The endoplasmic reticulum processes and packages proteins, and the Golgi apparatus finishes and ships cell products in vesicles. Organelles work together in an assembly line to produce proteins - the nucleus produces mRNA, ribosomes on the rough ER translate mRNA into proteins, and the Golgi apparatus packages and ships the finished proteins to their destinations. Membranes act as sites for chemical reactions and compartmentalize cellular functions.

1. IB BIO NOTES: Organelles of Cells 12/4/2012 9:17:00 AM
Types of Cells
Prokaryote bacteria cells – no organelles
Eukaryote animal cells
Eukaryote plant cells
Organelles
Specialized structures
o Specialized functions
 Cilia of flagella for locomotion
Containers
o Partition cell into compartments
o Create different local environments
o Distinct and incompatible functions
Membranes as sites for chemical reactions
o Unique combos of lipids and proteins
o Embedded enzymes & reaction centers
 Chloroplasts & mitochondria
Cells have jobs
Make proteins – proteins control every cell
Make energy –growth and life
Make more cells – growth repair renewal
Proteins do all the work
DNA codes for proteins which make cells
Cell functions
Building proteins
o Read DNA instructions
o Build proteins
o Process proteins
 Folding
 Modifying
o Address and transport proteins
Building Proteins
Organelles involved
o Nucleus
o Ribosomes
o Endoplasmic reticulum
o Golgi apparatus

2. o Vesicles
The Protein Assembly Line
o Nucleus->ribosome->ER->Golgi apparatus->vesicles
Nucleus
Function
o Protects DNA
Structure
o Double membrane
o Membrane fused in spots to create pores
 Allows large macromolecules to pass through
Nucleolus
Function
o Ribosome production
 Build ribosomes subunits from rRNA& proteins
 Exit through nuclear pores to cytoplasm and combine to
form functional ribosomes
Ribosomes
Function
o Protein production
Structure
o rRNA and protein
o 2 subunits combine
Types of Ribosomes
Free ribosomes
o Suspended in cytosol
o Synthesize proteins that function in cytosol
Bound ribosomes
o Attached to endoplasmic reticulum
o Synthesize proteins for export or for membranes
Endoplasmic Reticulum
Function
o Processes proteins
o Manufactures membranes
o Synthesis & hydrolysis of many compounds
Structure

3. o Membrane connected to nuclear envelope & extends
throughout cell
Rough ER
o Studded with ribosomes
o Produce proteins for export out of cell
 Protein secreting cells
 Packaged into transport vesicles for export
Smooth ER
o No ribosomes
o Membrane production
o Many metabolic processes
 Synthesis
 Synthesis lipids
 Hydrolysis
 Hydrolyze glycogen into glucose
 Detoxify drugs and poisons
Membrane Factory
Build new membrane
o Synthesize phospholipids
 Builds membranes
o ER membrane expands
 Bud off and transfer to other parts of cell that need
membranes
Golgi Apparatus
Function
o Finishes, sorts, tags, ships cell products
 Like ups shipping
o Ships products in vesicles
 Membrane sacs

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