$Entamoeba \ histolytica$ excretes through:

Taxonomists face difficulty in the classification of $..........$.

The 'Slipper animalcule' is:

By what process do organisms of the phylum Protozoa exhibit sexual reproduction?

Which of the following groups of kingdom $Protista$ is being described in the statements given below?
$(i)$ This group includes diatoms and golden algae.
$(ii)$ They are microscopic and float passively in water currents (plankton).
$(iii)$ Most of them are photosynthetic.
$(iv)$ They have deposits in their habitat; this accumulation over billions of years is referred to as 'diatomaceous earth'.

In which group of organisms does the cell wall form two thin overlapping shells that fit together?