General
The branch of biology that compares the genomes of different species.
What is comparative genomics?
The basic idea of DNA–DNA hybridisation is to measure how well strands from different species do this.
What is bind together (hybridise)?
These diagrams show evolutionary relationships based on genetic and/or morphological data.
What are phylogenetic trees?
DNA sequencing determines the exact order of these.
What are nucleotides (bases)?
rRNA stands for this.
What is ribosomal RNA?
These molecules (3) are compared in comparative genomics to determine relatedness.
What are DNA, RNA, and protein sequences?
This step is first in DNA–DNA hybridisation, before hybrid strands can form.
What is separating the DNA strands by heating?
The point on a phylogenetic tree where a single lineage splits.
What is a node?
The four DNA bases are represented by these letters.
What are A, T, C, and G?
rRNA is often used for comparing species because it evolves at this rate.
What is a slow (conserved) rate?
The term for the evolutionary history and relationships among species.
What is phylogeny?
A higher melting temperature in DNA–DNA hybridisation means this about the species compared.
What is they are more closely related?
The group that contains a single common ancestor and all of its descendants.
What is a clade?
The method developed by Frederick Sanger is a common way of doing this.
What is determining DNA sequences (Sanger sequencing)?
This rRNA subunit is commonly used in prokaryotic species comparison.
What is 16S rRNA?
Comparative genomics relies on the principle that more closely related species have more of these in common.
What are similarities in their genetic sequences?
The measure recorded in DNA–DNA hybridisation when the hybrid DNA separates.
What is the melting temperature?
In a phylogenetic tree, a shorter branch length usually means this.
What is a closer evolutionary relationship?
Sequencing data is compared between species to count these differences.
What are base pair differences?
rRNA sequencing is especially useful for determining relationships among these types of organisms.
What are distantly related species or ancient lineages?
The type of evidence comparative genomics provides that can be used alongside morphological evidence.
What is molecular evidence?
One disadvantage of DNA–DNA hybridisation is that it cannot give this type of genetic information.
What is the exact DNA sequence?
The root of a phylogenetic tree represents this
What is the most recent common ancestor of all species in the tree?
This modern technology allows rapid sequencing of large amounts of DNA.
What is next-generation sequencing (NGS)?
The slow mutation rate of rRNA means it is best for resolving these kinds of evolutionary relationships.
What are deep (long-term) divergences?