What are the key structures in the nucleas?
- Double membrane (nuclear envelope) & Pores
- Nucleolus
- Chromatin
What is the function of the pores in the double membrane?
They allow substances to enter & leave the nucleus
What substances enter the nucleas?
Ions
Amino acids
What substances leave the nucleas?
mRNA
rRNA
tRNA
What does the outer membrane extend to make?
The rough endoplasmic reticulum (ER)
The smooth ER
What is the function of the Nucleolus?
It synthesises Ribosomes
What is the function of ribosomes?
Ribosomes synthesise proteins
What is Chromatin formed by?
DNA and Histon proteins
What does DNA contain?
Instructions to make proteins
What is it called when DNA is read?
Transcription
What is formed when DNA is transcribed?
mRNA (messenger RNA)
What is DNA replication for?
Cell division
What is the rough endoplasmic reticulum (ER) made out of?
A system of flattened sacks formed as an extension of the outer membrane of the nuclear envelope
How can you tell the difference between the rough and smooth ER?
The rough ER surface is covered in Ribosomes.
What is the function of the ribosomes on the surface of the rough ER?
They synthesise proteins which travel through the rough ER and are folded. They are packaged into vesicles and sent to the Golgi Apparatus.
What does the smooth ER synthesise?
Lipids, Cholesterol & Steroid hormones
Bonus: another function -> detoxification
Describe the structure of the golgi apparatus.
A group of flattened sacks, vesicles can be seen on/at edge of the cis face to enter or the trans face to leave.
What is the overall function if the golgi apparatus?
Vesicles are recieved from ERs, modified, packaged and transported.
Which organelles are made of an extension of the nucleas outer membrane?
Smooth ER
Rough ER
Where are the vesicles transported from the golgi apparatus?
- out of the cell
- into the cell membrane
- stays in cell (lysosome)
Can you give me an example of the function of the golgi apparatus starting from the rough ER?
Rough ER sends a protein vesicle which enters the Golgi apparatus. Carbohydrate molecules are attached before the vesicles is packaged and sent to the pancreas as Insulin.
What is a Lysosome?
A type of Golgi vesicle containing digestive enzymes
What is the function of Lysosomes?
They break down waste material (worn out organelles or pathogens)
What does the membrane of lysosomes separate?
Digestives enzymes from the cytoplasm of the cell.
