Molecular phylogenetics is the branch of phylogeny that analyses genetic, hereditary molecular differences in DNA, mRNA or amino-acid sequences to gain information on an organism's evolutionary relationships.From these analyses, it is possible to hypothesise the processes by which diversity among species has been achieved. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree.Molecular phylogenetics makes inferences of the evolutionary relationships that arise due to molecular evolution and results in the construction of a phylogenetic tree.mRNA is coded for by DNA and is complementary to the base sequence on DNA, so the base sequences of mRNA molecules can be compared instead of comparing the base sequences of DNA.Only genes that are transcribed can be compared in this way and the introns will have been spliced out so the mRNA may not be an exact copy of the DNA.
Comparing mRNA
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Specification: AQA Biology (7401), AS-level, 3.4.7 Investigating diversity. Topic: Biodiversity.
Key terms in this lesson
- gene
- A length of DNA that codes for a polypeptide or a functional RNA molecule, at a specific locus on a chromosome.
- intron
- A non-coding sequence of DNA or pre-mRNA that is removed by splicing before translation.
- species
- A group of organisms with similar characteristics that can interbreed to produce fertile offspring.
- phylogeny
- The evolutionary relationship between organisms and their ancestors, often represented as a branching tree.
More in Biodiversity
- Balancing Conservation and Farming
- Managing Ecosystems
- Investigating Diversity
- Comparing DNA
- Comparing Amino-acids Sequences
- Sampling
- Random Sampling
- Normal Distribution
All 33 lessons in Biodiversity · All AQA AS-level Biology topics