#rough er

Here's some more old art lol! This was for a biology project earlier this year. It was about organelles. Some of it may not be 100% accurate but I got a 100! so that's all that counts :'>

IT WAS MY EXCUSE TO DRAW CUTE GIRLS IN CAMOUFLAGE AND MAKE DOOMED YURIs 😭😭😭😭😭😭😭

For example this is the diagram you have to learn so you can learn it like-

Each cell has a protective outer layer (plasma membrane) , so the cell only lets some certain things or nutrients into the system that it needs but keeps other things out (semipermeable).

Inside the animal cell there is the digestive system (cytoplasm), in the digestive system there is the working organs (organelles).

Tiny grains floating inside the system are called (ribosome) where protein is made.

The cell also has a DNA (nucleus) that contains all are genetic information the DNA is found on structures of the cell (nucleus) called chromosomes .

The nucleus is surrounded by a layer or cover (nuclear membrane) which controls what goes in and out.

Rough ER is a series of folded protective outer layer (membrane) rough ER is always spotted with the tiny grains floating around the system (ribosomes). Together the ribosomes and rough ER make new proteins and protective layer (membranes) that the system or cell needs.

While smooth ER is the opposite, it has vehicles which are used to move things around the digestive system (transport vesicles).

Now there is another working organ which helps in packaging up things, to be transported around cells or need to leave the cell like hormones (Golgi Apparatus).

Now comes lysosomes, lysosomes are both the vitamin c and the decomposer of the cell. It kills the bacteria that invades the body and it also break downs the THINGS that cell doesn 't need.

Vacuoles are large membranous sacs used to store things. While vesicles are smaller sacs.

Mitochondria is the powerhouse that breaks down sugar (ATP) which helps the cell get energy .

Rough ER (RER) is involved in some protein production, protein folding, quality control and despatch

Called ‘rough’ because studded with ribosomes

Smooth ER (SER) is associated with the production and metabolism of fats and steroid hormones

Smooth because no ribosomes and is associated with smooth, slippery fats.

STRUCTURE

Continuous membrane of flattened sacs (cisternae) and network tubules, touching nuclear membrane. 

Membrane bound ribosomes firmly attached to the outer cytosolic side of the RER

However these are constantly being bound and released - will only bind when specific protein-nucleic acid complex forms in cytosol 

FUNCTION

Proteins are made by the ribosomes on the surface of the RER - translation

Then (some) are threaded inside RER to be modified and transported

RER working with membrane bound ribosomes takes polypeptides and amino acids from the cytosol and continues protein assembly including, at an early stage, recognising a ‘destination label’ attached to each of them. 

Proteins are produced for the plasma membrane, Golgi apparatus, secretory vesicles, lysosomes, endosomes and the ER. 

Some  proteins into the lumen (inside) of the RER; others are processed in RER membrane itself

Lumen: some proteins have sugar groups added to form glycoproteins; some have metal groups added

EG: in RER four polypeptide chains are brought together to form haemoglobin.

Protein folding unit lumen of the rough ER: proteins folded to produce biochemical architecture which will provide ‘lock and key’ and other recognition and linking sites.

Protein quality control section

Lumen: incorrectly formed or incorrectly folded proteins rejected. 

Rejects stored in the lumen or sent for recycling for eventual breakdown to amino acids. 

A form of cystic fibrosis = missing single amino acid, phenylanaline, in a particular position in the protein construction. Quality control section spots the error and rejects, however individual would have been better off with poor product than none at all