The Structure of DNA

This set of flashcards covers key vocabulary and concepts from the lecture on the structure of DNA, its components, and related biological processes.

Nucleus

The cell organelle that houses DNA.

Nuclear Envelope

A phospholipid bilayer that surrounds the nucleus.

Nuclear Pores

Protein structures that allow transport between the nucleus and cytoplasm.

Nucleoplasm

The substance contained within the nucleus.

Nucleolus

A component of the nucleoplasm where ribosomal RNA synthesis occurs.

Chromatin

The combination of DNA and histone proteins that forms the structural basis of chromosomes.

Heterochromatin

Highly condensed chromatin that does not undergo transcription.

Euchromatin

Loosely packed chromatin that is actively transcribed.

Histone Proteins

Proteins around which DNA is tightly coiled to form nucleosomes.

Nucleosome

A unit of DNA coiled around a core of histone proteins.

Phosphate Group

The negatively charged component of a nucleotide that connects to the sugar backbone.

Nucleotide

A building block of DNA, consisting of a nitrogenous base, a pentose sugar, and a phosphate group.

Complementarity

The principle that adenine pairs with thymine and guanine pairs with cytosine in DNA.

Phosphodiester Bond

The strong bond that connects nucleotides in the DNA sugar-phosphate backbone.

Major Groove

The larger groove in the DNA double helix where proteins bind for replication and transcription.

Minor Groove

The smaller groove in the DNA double helix that also plays a role in protein binding.

Antiparallel Arrangement

The orientation of the two strands of DNA running in opposite directions.

Methylation

The addition of methyl groups to DNA which can inhibit gene transcription.

Acetylation

The addition of acetyl groups to histone proteins, leading to relaxed DNA structure and increased transcription.

Drug-induced lupus

An autoimmune response triggered by certain drugs that target histone proteins.

Huntington's disease

A genetic disorder linked to increased deacetylation of histone proteins, leading to decreased transcription.