DNA Structure and Discovery

These flashcards cover key vocabulary terms related to the structure and discovery of DNA, including definitions and important concepts from the lecture.

DNA

Deoxyribonucleic acid, the molecule that carries genetic information in living organisms.

Double Helix

The structure formed by two strands of DNA that spiral around each other.

Nucleotide

The basic building block of DNA, consisting of a five-carbon sugar, a phosphate group, and a nitrogenous base.

Deoxyribose

The sugar component of DNA nucleotides, lacking a hydroxyl group at the 2' carbon.

Phosphodiester bond

The type of covalent bond that links nucleotides in a DNA strand.

Watson and Crick

The scientists who discovered the double helical structure of DNA.

Hydrogen bonding

The non-covalent attraction between a hydrogen atom and an electronegative atom, crucial for base pairing in DNA.

Base pair

Two complementary nitrogenous bases bonded together in the DNA structure.

Pyrimidines

The class of nitrogenous bases that includes thymine and cytosine, characterized by a single ring structure.

Purines

The class of nitrogenous bases that includes adenine and guanine, characterized by a double ring structure.

Major groove

The wider of the two grooves in the DNA double helix, containing specific binding sites for proteins.

Minor groove

The narrower of the two grooves in the DNA double helix, generally non-specific for protein binding.

X-ray crystallography

A technique used to determine the atomic structure of a crystal, including DNA.

Chargaff's rules

The observation that in DNA, the amount of adenine equals thymine and the amount of guanine equals cytosine.

Franklin's photo 51

The famous X-ray diffraction image taken by Rosalind Franklin that provided critical evidence for the helical structure of DNA.

Mutation

A change in the DNA sequence that can lead to variation in traits.