The taxonomic hierarchy and kingdoms
| English | Chinese | Pinyin |
|---|---|---|
| taxonomic hierarchy | 分类层级 | fēn lèi céng jí |
| kingdom | 界 | jiè |
| phylum | 门 | mén |
| genus | 属 | shǔ |
| Protoctista | 原生生物界 | yuán shēng shēng wù jiè |
| Fungi | 真菌界 | zhēn jùn jiè |
| photosynthesis | 光合作用 | guāng hé zuò yòng |
Sorting all of life
- Inside the Eukarya, organisms are sorted into smaller and smaller groups.
- This is the taxonomic hierarchy 分类层级.
- The Eukarya split into four kingdoms 界.
The smallest, most specific group in the taxonomic hierarchy is the ______.
Domain → kingdom → phylum → class → order → family → genus → species.
Kingdom to species
- The levels: Kingdom → Phylum 门 → Class → Order → Family → Genus 属 → Species.
- Each level is a smaller, more closely related group, ending at a single species.
The taxonomic hierarchy
Step down the levels for one species — humans — from the broadest domain to the most specific species.
Put the taxonomic levels in order, from broadest to most specific.
Kingdom → Phylum → Class → Order → Family → Genus → Species (broad to specific).
Which level is the smallest, most closely related group?
Species is the most specific level; kingdom is the broadest.
Two organisms in the same genus are more closely related than two that only share the same class.
The further down the hierarchy two organisms still match, the more closely related they are.
The four eukaryote kingdoms
- Protoctista 原生生物界 — mostly single-celled (e.g. Amoeba).
- Fungi 真菌界 — feed by absorbing food; cell walls of chitin.
- Plantae — make their own food by photosynthesis 光合作用.
- Animalia — feed on other organisms.
A museum insect collection: classification groups organisms by shared features.
Which kingdom makes its own food by photosynthesis?
Plantae photosynthesise; Animalia feed on others; Fungi absorb food; Protoctista are mostly single-celled.
Match each kingdom to how it feeds.
Plantae photosynthesise; Fungi absorb; Animalia feed on other organisms; Protoctista are a mixed group.
Why classification changes
- New evidence — especially DNA and protein comparisons — can reveal true relationships.
- Organisms are reclassified when the evidence shows the old grouping was wrong.
You've got it
- hierarchy: Kingdom → Phylum → Class → Order → Family → Genus → Species (broad → specific)
- four eukaryote kingdoms: Protoctista, Fungi (absorb), Plantae (photosynthesise), Animalia (feed on others)