The first evolved eukaryotes are:

Match the following columns:

Column-$I$ (Group)	Column-$II$ (Example/Characteristic)
$P$. Chrysophytes	$I$. Euglena
$Q$. Dinoflagellates	$II$. Diatoms,Desmids
$R$. Euglenoids	$III$. Physarum (Slime mold)
$S$. Slime molds	$IV$. Gonyaulax

Suppose you accidentally find an old preserved permanent slide without a label. In your effort to identify it,you place the slide under a microscope and observe the following features:
$(a)$ Unicellular
$(b)$ Well-defined nucleus
$(c)$ Biflagellate - one flagellum lying longitudinally and the other transversely.
What would you identify it as? Can you name the kingdom it belongs to?

Diatoms are also called 'Pearls of Ocean'. Why? What is diatomaceous earth?

Select the correct option for the following statements:
$(i)$ All protozoans are heterotrophs and live as predators or parasites.
$(ii)$ $Trypanosoma$ causes sleeping sickness.

Contractile vacuole is generally absent in the