DNA Structure and Function

These flashcards cover the essential vocabulary related to the structure and function of DNA, facilitating review and understanding of key concepts.

Double Helix

The shape of DNA, consisting of two spiral strands made up of nucleotides.

Complementary Base Pairing

The specific hydrogen bonding between bases; adenine pairs with thymine (A-T), and cytosine pairs with guanine (C-G).

Phosphodiester Bonds

Covalent bonds between the sugar of one nucleotide and the phosphate group of another, forming the sugar-phosphate backbone.

Nucleotides

The monomers that make up DNA and RNA, consisting of a sugar, a phosphate group, and a nitrogenous base.

Sugar-Phosphate Backbone

The structural framework of DNA and RNA, formed by alternating sugar and phosphate groups linked by phosphodiester bonds.

Polynucleotide

A polymer consisting of many nucleotide monomers linked together, forming a strand of DNA or RNA.

3’ and 5’ Polarity

Refers to the orientation of the two ends of a DNA or RNA strand; the 3’ end has a hydroxyl group, while the 5’ end has a phosphate group.

Antiparallel Strands

DNA strands that run in opposite directions, with one strand oriented 5' to 3' and the other 3' to 5'.

Covalent Bonding

A type of strong bond formed between atoms when they share electrons, essential for the sugar-phosphate backbone of DNA.

Hydrogen Bonding

A type of weak bond that occurs between complementary base pairs in DNA, stabilizing its structure.

Adenine (A)

A nitrogenous base in DNA, pairs with thymine (T).

Thymine (T)

A nitrogenous base in DNA, pairs with adenine (A).

Cytosine (C)

A nitrogenous base in DNA, pairs with guanine (G).

Guanine (G)

A nitrogenous base in DNA, pairs with cytosine (C).

RNA

Ribonucleic acid, a polymer of ribonucleotide monomers, usually single-stranded, which plays various roles in cellular function.

Deoxyribose

The sugar component of DNA nucleotides, lacking an oxygen atom compared to ribose.

Ribose

The sugar component of RNA nucleotides, which has an extra hydroxyl group.

Uracil (U)

A nitrogenous base in RNA that replaces thymine (T) found in DNA.

Phosphate Group

A component of nucleotides that carries a negative charge, making nucleic acids polar.

X-Ray Crystallography

A technique used to determine the molecular structure of DNA, crucially utilized by Franklin and Wilkins.

Watson and Crick

Scientists who proposed the double helix structure of DNA in 1953.

Base Pairing

The specific pairing of nitrogenous bases in DNA, essential for DNA replication and function.