Nucleic Acid Structure and DNA Packaging

This set of flashcards covers key concepts related to nucleic acids and DNA structure, function, and packaging.

Nucleic Acids

Molecules that constitute the genetic material of living organisms, including DNA and RNA.

Deoxyribonucleic acid (DNA)

A type of nucleic acid that contains the genetic instructions for living organisms.

Ribonucleic acid (RNA)

A nucleic acid involved in the synthesis of proteins, primarily involved in transferring the genetic code from DNA.

Chromatin

A complex of DNA and histone proteins that make up chromosomes.

Chromosomes

Threadlike structures that contain tightly wound and packed chromatin.

Nucleotide

The monomer unit of nucleic acids, composed of a nitrogenous base, a pentose sugar, and one or more phosphate groups.

Nitrogenous bases

The components of nucleotides that include pyrimidines (cytosine, thymine in DNA, uracil in RNA) and purines (adenine and guanine).

5’ phosphate group

The end of a DNA strand that has a phosphate group attached to the fifth carbon of the sugar.

3’ hydroxyl group

The end of a DNA strand that has a hydroxyl group attached to the third carbon of the sugar.

Double Helix Structure

The twisted ladder shape of DNA, formed by two strands of nucleotides bound together by hydrogen bonds.

Antiparallel orientation

The opposite direction of the two DNA strands, where one strand runs 5' to 3' and the other runs 3' to 5'.

Base pairing

The specific hydrogen bonding between nitrogenous bases; adenine pairs with thymine, and guanine pairs with cytosine.

Nucleosomes

Structures formed when linear chromosomal DNA wraps around octamer histone proteins.

Solenoid shape

The coiled formation of nucleosomes in eukaryotic DNA packaging.

Eukaryotic chromosome

The fully compacted structure formed by DNA and packaging proteins in the nucleus.