Cell Specialisation (Pt. 2) Flashcards
What is the function of nuclear envelopes?
- Protect genetic material
- Gene expression control
- Efficient endomembrane system
- Controls molecular exchange
What is the function of nuclear pores?
- Channels for molecule transport
- Coordinates gene expression
What is the structure of the nucleus?
It is the shape of a chromatin in nucleoplasm
What is the advantage of the double membrane?
It allows the breakdown and reformation of the nuclear membrane during cell division of mitosis and meiosis.
What is the function of ribosomes?
It is the site of protein synthesis
What is the structure of the ribosome?
It is composed of protein and ribosomal RNA (rRNA)
- Has a small subunit that binds to the mRNA
- Has a large subunit that binds to tRNA
Forms a complex for translation
What is the size of ribosomes?
Eukaryote: 80s
Prokaryote: 70s
What is the ribosome’s location in the eukaryotes?
Free Ribosomes - In the cytosol; it synthesizes proteins for intracellular use
Bound Ribosomes - Embedded in the Rough ER; synthesize proteins for packaging into vesicles and transport
What is the function of a Golgi Apparatus?
Responsible for sorting, modifying, and exporting cellular materials.
How does the Golgi Apparatus sort organisms?
By receiving the proteins and lipids
What does the Golgi Apparatus modify?
It modifies proteins and lipids into functional molecules
How does the Golgi Apparatus export materials?
- Constitutive secretions: Direct/immediate release
- Regulatory secretion: Materials are stored and then released in response to external signals
What is the structure of a Golgi Apparatus?
It is composed of flattened sacs located between the ER (cis facing) and plasma membrane (trans facing)
What are vesicles?
They are membrane-wrapped containers transporting materials between cell compartments
What is a Clathrin?
Coat protein involved in vesicle formation?
