BCMB 311 Test 4 Questions with Verified Correct
Answer
Why do cells have separate compartments?
To separate incompatible reactions and control pathways independently.
What are the three types of protein transport?
Through nuclear pores, across membranes, and by vesicles.
Which transport method requires proteins to unfold?
Transport across membranes, such as into mitochondria.
Do proteins unfold during nuclear pore transport?
No. They can remain folded.
What is a signal sequence?
An amino acid pattern that directs a protein to its destination.
What is a sequence motif?
A sequence pattern with a specific biological function.
What does 'necessary' mean for a signal sequence?
Without it, the protein cannot be correctly targeted.
What does 'sufficient' mean for a signal sequence?
Adding it to another protein can redirect that protein.
, Where do proteins without a targeting signal generally remain?
In the cytosol.
What is the nuclear envelope?
A double membrane surrounding the nucleus.
What is the nuclear lamina?
A supportive filament meshwork lining the inside of the nucleus.
What does the nuclear pore complex (NPC) do?
Controls movement of materials into and out of the nucleus.
What do fibrils on nuclear pores help do?
Recognize and interact with transport receptors carrying cargo.
What is an NLS?
A nuclear localization signal that targets a protein to the nucleus.
What recognizes a protein's NLS?
A nuclear import receptor.
How does a nuclear import receptor help cargo enter?
It binds the cargo and interacts with the nuclear pore.
What causes nuclear import cargo to be released?
Ran-GTP binds the import receptor inside the nucleus.
Answer
Why do cells have separate compartments?
To separate incompatible reactions and control pathways independently.
What are the three types of protein transport?
Through nuclear pores, across membranes, and by vesicles.
Which transport method requires proteins to unfold?
Transport across membranes, such as into mitochondria.
Do proteins unfold during nuclear pore transport?
No. They can remain folded.
What is a signal sequence?
An amino acid pattern that directs a protein to its destination.
What is a sequence motif?
A sequence pattern with a specific biological function.
What does 'necessary' mean for a signal sequence?
Without it, the protein cannot be correctly targeted.
What does 'sufficient' mean for a signal sequence?
Adding it to another protein can redirect that protein.
, Where do proteins without a targeting signal generally remain?
In the cytosol.
What is the nuclear envelope?
A double membrane surrounding the nucleus.
What is the nuclear lamina?
A supportive filament meshwork lining the inside of the nucleus.
What does the nuclear pore complex (NPC) do?
Controls movement of materials into and out of the nucleus.
What do fibrils on nuclear pores help do?
Recognize and interact with transport receptors carrying cargo.
What is an NLS?
A nuclear localization signal that targets a protein to the nucleus.
What recognizes a protein's NLS?
A nuclear import receptor.
How does a nuclear import receptor help cargo enter?
It binds the cargo and interacts with the nuclear pore.
What causes nuclear import cargo to be released?
Ran-GTP binds the import receptor inside the nucleus.
