In which of the following organisms is the presence of a rigid cell wall observed?

Bacteria and yeast are similar in all features except one. Identify the exception.

Which of the following domains lacks a cell wall?

Match the scientists given in column $I$ with their discovery given in column $II$ and choose the correct option.

Column-$I$ (Scientists)	Column-$II$ (Discovery)
$A$. Ernst Mayr	$I$. Discovered Viroids
$B$. Whittaker	$II$. Gave the name virus
$C$. Ivanowsky	$III$. Proposed five kingdom classification
$D$. Diener	$IV$. Evolutionary biology

Cell division is the mode of reproduction in

Which of the following statements are incorrect based on the Whittaker classification system?
$I.$ Whittaker classified organisms into unicellular and multicellular based on the complexity of cell structure.
$II.$ Whittaker classified organisms as producers,decomposers,and consumers based on their ecological roles.
$III.$ Organisms were divided into unicellular and multicellular based on the complexity of body organization.
$IV.$ Prokaryotic and eukaryotic organisms were divided based on their mode of nutrition.