Endoplasmic Reticulum & Protein Synthesis Flashcards
Main function of ER?
Synthesis of protein and lipid molecules.
Two types of ER are…
Rough ER and Smooth ER
Which type is involved with protein synthesis?
Rough ER. Studded with ribosomes.
SER is involved in…
lipid molecules.
Translation of mRNA into protein is carried out by…
ribosomes.
How are amino acids linked in protein synthesis?
With the aid of a ribosome which works with the mRNA to express the gene.
What does the small subunit do?
Reads the mRNA.
What does the large subunit do?
Catalyses the addition of the amino acid on the growing amino acid chain. (Peptidyl transferase)
What does the secretory pathway consist of?
- Proteins secreted from the cell
- Proteins resident in the lumen of the ER and Golgi complex
- Integral proteins in the membranes of the ER, Golgi & plasma membrane
Non-secretory pathway is?
Targeting to an intracellular organelle.
Sequence of secretory pathway?
Ribosome to ER. After packaging into transport vesicles, they go to the Golgi. Then further sorted to plasma membrane or lysosomes.
Function of signal sequences?
Allows proteins to be shipped to the correct location where it is needed.
