🧬 6. DNA Packaging and Epigenetics

Nuclear envelope

Definition: The membrane surrounding the nucleus.
A double membrane separating the nucleus from the cytoplasm.

Nuclear pores

Definition: Openings in the nuclear envelope.
Answer: Control movement of molecules into and out of the nucleus.

Definition: Openings in the nuclear envelope.
Control movement of molecules into and out of the nucleus.

Chromatin

Definition: DNA associated with proteins.
DNA + histone and other proteins that organize DNA.

Telomere

Definition: Protective DNA sequence at the end of a chromosome.
Helps protect chromosome ends from degradation and improper joining.

Centromere

Definition: A specialized chromosome region.
Important for chromosome organization and separation during cell division.

Epigenetics

Definition: Regulation of gene expression without changing the DNA sequence.

Answer: Changes such as DNA methylation and histone modification can affect gene activity.

DNA methylation

Definition: Addition of methyl groups to DNA.
An epigenetic modification that can affect gene expression.

Histone modification

Definition: Chemical modification of histone proteins.

Can change how tightly DNA is packaged and affect gene expression.

Nucleus as an organized organelle

Definition: The role of the nucleus in organizing genetic material.
The nucleus organizes DNA and controls processes such as replication and transcription.