Cell organelles

The table below summarises the main functions of the major cell organelles:

Organelle/macromolecule	Main function
Endoplasmic reticulum	Rough endoplasmic reticulum translation and folding of new proteins manufacture of lysosomal enzymes site of N-linked glycosylation examples of cells with extensive RER include pancreatic cells, goblet cells, plasma cells Smooth endoplasmic reticulum steroid, lipid synthesis examples of cells with extensive SER include those of the adrenal cortex, hepatocytes, testes, ovaries
Golgi apparatus	Modifies, sorts, and packages these molecules that are destined for cell secretion Site of O-linked glycosylation
Mitochondria	Aerobic respiration. Contains mitochondrial genome as circular DNA
Nucleus	DNA maintenance and RNA transcription
Lysosome	Breakdown of large molecules such as proteins and polysaccharides
Nucleolus	Ribosome production
Ribosome	Translation of RNA into proteins
Peroxisome	Catabolism of very long chain fatty acids and amino acids Results in the formation of hydrogen peroxide
Proteasome	Along with the lysosome pathway involved in degradation of protein molecules that have been tagged with ubiquitin