DNA as Phylogenetic Information

These flashcards cover key vocabulary and concepts related to the structure, function, and significance of DNA in biology and evolution.

DNA (deoxyribonucleic acid)

A polymer made up of repeating subunits called nucleotides, which serves as the molecular basis of heredity.

Nucleotide

The building block of DNA, consisting of a sugar (deoxyribose), a phosphate group, and a nitrogenous base.

Double helix

The twisted structure of DNA formed by two antiparallel strands.

Base pairing rules

The rules dictating that adenine pairs with thymine (A-T) and cytosine pairs with guanine (C-G) in DNA.

Antiparallel strands

Strands of DNA that run in opposite directions; one runs 5′ to 3′ and the other runs 3′ to 5′.

Hydrogen bonds

Weak bonds that form between the nitrogenous bases of DNA, allowing the strands to separate easily.

DNA replication

The process by which DNA makes a copy of itself, producing two identical double helices.

Semiconservative replication

The mode of replication in which each new DNA molecule contains one parental strand and one new strand.

Transcription

The process of copying a segment of DNA into messenger RNA (mRNA).

Translation

The process by which ribosomes read mRNA to synthesize proteins based on codon sequences.

Codon

A group of three nucleotide bases in mRNA that specifies one amino acid.

Mutation

A change in the nucleotide sequence of DNA, which can affect the function of genes.

Point mutation

A small mutation affecting a single nucleotide in the DNA sequence.

Silent mutation

A mutation that does not change the amino acid sequence despite changing a codon.

Phylogenetic analysis

The study of evolutionary relationships among biological entities, often using DNA sequence comparisons.

Conserved regions

Segments of DNA that remain unchanged across different species, indicating shared ancestry.

Introns

Non-coding regions of DNA that are removed before protein translation.

Junk DNA

DNA sequences with no known function, which can mutate freely and serve as markers for evolutionary studies.