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Classification and evolution

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Question 1

Organisms are classified into three domains: Archaea, Bacteria, and Eukarya.

Scientists compared several molecular and cellular features across these three domains to determine their evolutionary relationships.

a.

The table shows a comparison of some features of the three domains:

FeatureArchaeaBacteriaEukarya
Histones associated with DNAPresent in some speciesAbsentPresent
Introns in genesPresent in some speciesAbsentPresent
Sensitivity to streptomycin/chloramphenicolNoYesNo
Chromosome structureCircularCircularLinear
Membrane lipid hydrocarbon chainBranchedUnbranchedUnbranched

Explain what conclusions can be drawn from the table about which domains are most closely related.

[3]
b.

State the roles of histones and ribosomes in cells.

[2]

Classification and evolution Questions

  1. A Level
  2. /Biology
  3. /Classification and evolution