Compare Kingdoms and Classification Evidence
Classification systems improve when cell organisation, nutrition and evolutionary evidence are considered together.
Kingdom Classification is the central idea in this question pattern. Identify the condition in the stem before applying the method below.
Compare metabolic roles
Photosynthetic autotrophs occur in Plantae, many Protista and photosynthetic bacteria. Chemoautotrophy occurs among prokaryotes in Bacteria and Archaea. In the six-kingdom scheme used by this question, the respective counts are three and two.
Read the five-kingdom distinctions
The five-kingdom scheme separates Chlamydomonas (Protista) from Spirogyra (Plantae). Cyanobacteria may have a gelatinous sheath; bacteria include nitrogen-fixing partners and antibiotic producers. Most heterotrophic bacteria use organic matter, not inorganic matter.
Why classifications change
Older two-kingdom systems grouped many organisms as plants partly because they had cell walls. Modern systems incorporate cellular organisation and phylogenetic relationships alongside morphology, physiology and reproduction.
OlympIQ exam lens
- ✓Photosynthetic autotrophs span three kingdoms; chemoautotrophs span two in the six-kingdom framing.
- ✓Chlamydomonas and Spirogyra fall in different five-kingdom groups.
- ✓Heterotrophy uses organic material.
- ✓Classification incorporates phylogenetic evidence.
Check which kingdom scheme the question names before counting groups.
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