Protein Synthesis
Step 1
Nucleus
Intial stage of protein synthesis. Gene makes a small strand of messenger MRNA, through the process of transcription.
Step 3: Ribosomes
Free Ribosomes: scattered through the cytoplasm, convert MRNA to protein, to be used throughout JUST the cell.
Fixed Ribosomes: Converts MNRA to protein, then sends to the Rough Endoplasmic Reticulum.
Translation (cytoplasm)
Step 2
MRNA leaves the nucleus through paws in the membrane, attaching to Ribosomes.
Step 4:
Endoplasmic Reticulum
Rough Endoplasmic Reticulum: proteins synthesised by fixed ribosomes are sent here. Here they are modified and then sent further to the Golgi apparatus.
Step 5:
Golgi apparatus
Proteins are further modified and packaged here in vesicles. There are 3 types of vesicles. Vesicles are then carried away, where one type of vesicle becomes a lysosome.
Step 6
Types of Vesicles / Plasma Membrane
Secretory Vesicle: fuses to membrane and empties contents into extracellular space.
Membrane Renewal Vesicle: add new proteins and (lipids) to plasma membrane.
Lysosome: engulf waste products and breaks them down