Distinguish between Archaea and Eukarya.

Label the parts of the cell walls in Gram-positive Eubacteria and Gram-negative Eubacteria shown below.

a. membrane-bound organelles present in Eukarya but absent in Archaea;

b. 70S ribosomes in Archaea whereas 80S ribosomes in (cytoplasm of) Eukarya;

c. nuclear envelope in Eukarya, not in Archaea;

d. introns are present in Eukarya but only in some genes of Archaea;

e. histone proteins present in all Eukarya but only in a few Archaea;

f. the membrane lipid structure is unbranched in Eukarya but branched in Archaea;

g. Archaea can inhabit extreme habitats while Eukarya cannot;

I. peptidoglycan;

II. outer membrane/layer of lipopolysaccharide and protein;

III. peptidoglycan;

Many candidates were not able to distinguish between Archaea and Eukarya. A few mentioned the different size ribosomes but that was all.

Labelling the part of the Gram-positive and Gram-negative cell walls was a problem as many candidates did not know the names of the layers.