Nucleus and Genomes

Question 1

What is the role of the nucleus?

Answer 1

Gene expression and the regulation of genome activity

Question 2

What is the nucleus the site of?

Answer 2

• DNA replication
• RNA synthesis
• RNA processing
• ribosome assembly

Question 3

What does the nuclear envelope do?

Answer 3

separates the contents of the nucleus from the cytoplasm

Question 4

What establishes nuclear composition?

Answer 4

The selective traffic of proteins and RNAs through nuclear pore complexes in the nuclear envelope.

Question 5

What does the nuclear envelope consist of?

Answer 5

Two phospholipid bilayer membranes, an underlying nuclear lamina (protein framework), and nuclear pore complexes

Question 6

outer vs inner membrane of the nuclear envelope

Answer 6

Outer membrane: continuous with the endoplasmic reticulum. It is enriched in membrane proteins that bind the cytoskeleton.
Inner membrane: has membranes that bind to the nuclear lamina.

Question 7

How are nuclear pore complexes organized?

Answer 7

Organized into 8 spokes surrounding a central channel, with the spokes connected to protein rings at both the cytoplasmic and nuclear side.
Anchored at fusion.

Question 8

What is the nucleolus the site of?

Answer 8

rRNA transcription, rRNA processing, and ribosome assembly

Question 9

What is the nuclear lamina composed of? What does it do?

Answer 9

Composed of fibrous proteins called lamins and other proteins.
Provides structural support.