The largest functional compartment in eukaryotic animal cells
where is the cytosol
between recognizable cytoplasmic organelles
What does the cytosol consist of?
primarily moderately dark-staining material containing proteins, other macromolecules, small molecules, ions, and water
Where does glycolysis occur?
in the cytosol
what occurs in the cytosol
glycolysis and many other general metabolic processes
Where are free ribosomes?
scattered in the cytosol
what do free ribosomes look like?
more darkly stained granules of approximately 25 nm in diameter.
What are all of the proteins that will function in the cytosol, nucleus, and peroxisomes made on?
what are proteins that will be imported from the cytosol into mitochondria and chloroplasts made on?
Who can polyribosomes appear in routine electron micrographs
clusters, linear arrays, or rosettes
How are free ribosomes that are engaged in protein synthesis arranged
Smooth endoplasmic reticulum
irregular tubes and flattened sacs or cisterni of cytoplasmic membrane
Which type of endoplasmic reticulum has ribosomes on the surface
Where does the synthesis of phospholipids and part of the synthesis of steroids occur?
of the surface of the endoplasmic reticulum (rough and smooth)
What does enzymes associated with sER involved in?
detoxifying many foreign molecules such as drugs
Rough endoplasmic reticulum
consists of flattened sacs of cytoplasmic membrane with ribosomes associated with the cytoplasmic surface
What do the ribosomes on the rER do?
they are the site of synthesis of proteins that will be packaged by the golgi bodies
do the ribosomes on the rER appear to be permanently attached?
how/when does the ribosome attach to the rER
if the polypeptide currently being synthesized by the ribosome carries a signal sequence of amino acids near its amino terminal end that triggers uptake of the polypeptide into the rER
What happens after the polypeptide is taken into the rER
the initial oligosaccharide groups are added to glycoproteins prior to their transfer to Golgi bodies