DNA Packaging in Bacteria and Eukaryotes

Flashcards covering the key vocabulary and concepts related to DNA packaging in bacteria and eukaryotes.

Nucleoid

The region in a prokaryotic cell where the circular chromosomal DNA is located.

Intergenic regions

The short regions between adjacent genes on a chromosome.

Supercoiling

The coiling of double-stranded DNA on itself due to torsional stress, can be positive (overwinding) or negative (underwinding).

Telomere

Specialized sequences located at both ends of a linear chromosome that protect it from degradation.

Centromere

A region of the chromosome that forms the attachment point for spindle fibers during cell division.

Diploid

A cell or organism that has two sets of chromosomes, one from each parent.

Transposon

A segment of DNA that can move around to different positions within the genome of a single cell.

Retrotransposon

A type of transposon that uses an RNA intermediate to replicate and insert itself into new locations in the genome.

Gene expression

The process by which information from a gene is used to synthesize a functional gene product, typically a protein.

Euchromatin

Less condensed form of chromatin that is transcriptionally active.

Heterochromatin

Tightly packed form of DNA, which comes in two varieties: constitutive and facultative, often transcriptionally inactive.

Transposable elements (TEs)

Sequences of DNA that can change their position within the genome, potentially causing mutations and altering gene expression.

Exon shuffling

A phenomenon where transposable elements insert exons into a gene's coding sequence, leading to new gene functions.

Chromosomal rearrangements

Changes in the structure of chromosomes which may occur due to the movement of transposable elements.

Origins of replication

Specific locations on the chromosome where DNA replication begins.