The Nucleus Flashcards
What are the three primary functions of the nucleus?
- Storage, replication, and repair of genetic material
- Expression of genetic material
- Ribosome biosynthesis
What are the three things considered to be the nuclear content?
- Chromatin
- Nucleoplasm
- Nucleolus
Which structure is responsible for separating the nuclear content from the cytoplasm?
The nuclear envelope
What kind of barrier is the nuclear envelope?
Selective barrier
Which layer of the nuclear envelope binds ribosomes and is continuous with the rough ER?
The outer nuclear membrane
Which layer of the nuclear envelope has integral proteins and connects to nuclear lamina?
The inner nuclear membrane
What is the primary role of the nuclear lamina?
To support the nuclear envelope
What is the structure of the nuclear lamina?
It’s a thin meshwork of filamentous proteins
What is the nuclear lamina composed of in animal cells?
Lamins (intermediate filaments)
Do plants have a nuclear lamina?
Yes
Is the nuclear lamina of plants also composed of lamins?
No
How is the nuclear lamina bound to the nuclear envelope?
By integral membrane proteins
What is formed where the inner and outer nuclear membrane fuse?
Nuclear pores
What is the nuclear pore complex largely composed of?
Nucleoporins
What are nucleoporins?
A large group of proteins that make up the nuclear pore complex
What are the three types of nucleoporins?
- Structural nucleoporins
- Membrane nucleoporins
- F-G nucleoporins
What forms the nuclear basket?
Eight filaments that extend into the nucleoplasm with their distal ends joined by a terminal ring
Which type of nucleoporin forms the scaffold of the nuclear pore?
Structural nucleoporins
Which type of nucleoporin create an opening for movement of molecules into and out of the nucleus?
Structural nucleoporins
Which type of nucleoporin is embedded in the region where the inner and outer membranes of the nuclear envelope connect at the NPC?
Membrane nucleoporins
Which type of nucleoporin resides on the inner surface of the nuclear pore complex?
FG-nucleoporins
Which type of nucleoporin is associated with the nuclear basket and cytoplasmic filaments?
FG-nucleoporins
What is the largest structure inside the nucleus of eukaryotic cells?
The nucleolus
What is the primary function of the nucleolus?
Ribosome biosynthesis
