[Topic 4] Biodiversity and Natural Resources
, A Level Notes BNR: Classification + Taxonomy Biology
Taxonomy is the classification of living organisms into groups based on shared features
Hierarchy of groups:
The Binomial System
1) Domain Divine
2) Kingdom King Linnaeus (a Swedish botanist) came up
3) Phylum (plural; phyla) Prawn with a universal system to name (classify)
4) Class Curry different species.
5) Order Or
6) Family Fat 1) Generic name; Genus
7) Genus (plural; genera) Greasy 2) Specific name; Species
8) Species Sausages
The Five Kingdoms
1) Animalia Heterotrophs Obtain energy as ‘ready-made’ organic molecules
Ingest material from other organisms
2) Plantae Autotrophs Make own organic molecules by photosynthesis
3) Fungi Heterotrophs Absorb nutrients from decaying matter after external digestion
4) Protoctista Eukaryotes Photosynthesise/feed on organic sources not in other kingdoms
5) Prokaryotae Prokaryotes Include bacteria and blue-green bacteria (cyanobacteria)
Phylogenetic trees show evolutionary history and ancestral links between organisms
Three Domain Model & Molecular Phylogeny → Proposed by Carl Wosse
3 domains, Bacteria, Archaea and Eukaryota, classified by looking at …
The study of evolutionary relationships among organisms by looking at
similarities/differences between molecules such as:
• RNA/DNA sequences which are conserved in that domain
• Proteins such as ribosome size
• Cell wall structure
Molecular phylogeny can be used to determine relationships between two organisms:
✓ By comparing sequences of DNA bases (nucleotides) / amino acids in proteins
✓ The more similarities in common the more closely-related the subspecies
✓ (ALLOW) More recently evolved from common ancestor