Lesson 2 - Cytoplasmic organelles Flashcards
What are all the organelles called that are inside the cell?
Intracytoplasmic organelles
Example of intracytoplasmic organelles
Lysosomes
Mitochondria
What do the endoplasmic reticulum and golgi apparatus look like?
Maze-like structures
Plasma membrane is what kind of bilayer
lipoprotein bilayer
In the Smooth Endoplasmic Reticulum, the lipoprotein bilayers are thinner than:
thinner than cell membranes
2 surfaces of the SER
Cytoplasmic (Outer surface)
Luminal (inside surface)
3 forms of SER
- Vesicular (grain-like)
- Lamellar (sheet-like, layers)
- Tubular (tubes)
General function of the ER
Act as the second-in command to the nucleus: transport to and from the nucleus
5 Main functions of the SER
- Metabolism of small molecules
- Cellular detoxification - very high levels of a certain substance like sugar breaks it down into manageable levels .e.g alcohol is broken down into urine, breath.
- Fat (lipid) synthesis
- Manufactures steroid hormones
- Breaks down glycogen (glycogenolysis)
The 3 specialised forms of SER are:
freely convertible, meaning that the SER is a highly dynamic pleomorphic (able to assume different forms) organelle
Why is the RER rough?
Because there’s small cellular organelles on its wall called ribosomes. These ribosomes have black dots on them which appears rough, hence the name.
By what protein are ribosomes attached to the RER?
Ribophorin
Because the RER has ribosomes on it, the RER’s 3 functions are:
Protein processing
Preparing proteins for transport
Manufactures enzymes for lysosomes (vesicles/organelles that help with digestion_
What is the main enzyme constituent of the endoplasmic reticular membrane?
G6P (glucose) - used to break down glucose
Process of protein synthesis
When a nucleus needs nutrients, RNA is sent from 3’ end to 5’ end to ER. This attracts ribosomes.
A molecule then deactivates the ribosome.
As the ribosome gets closer to the RER, the ribosome attaches to a membrane protein.
A codon is then squirted out which says which protein is required.
The ER now knows what protein is required so it collects all the amino acids and forms a protein
Ribosomes then keep moving and get recycled into the endoplasmic reticulum to be used again