(a) List in tabular form two differences between binary fission and multiple fission.

(b) What happens when a mature Spirogyra filament attains considerable length.

3 mL of ethanol is taken in a test tube and warmed gently in a water bath. A 5% solution of alkaline potassium permanganate is added first drop by drop to this solution, then in excess.

(i) How is 5 % solution of KMnO₄, prepared?

(ii) State the role of alkaline potassium permanganate in this reaction. What happens on adding it in excess?

(iii) Write chemical equation of this reaction.

A squirrel is in a scary situation. Its body has to prepare for either fighting or running away. State the immediate changes that take place in its body so that the squirrel is able to either fight or run?

OR

Why is chemical communication better than electrical impulses as a means of communication between cells in a multi cellular organism?

What are homologous structures? Give an example. Is it necessary that homologous structures always have a common ancestor. Justify your answer.

Why is Tyndall effect shown by colloidal particles? State four instances of observing the Tyndall effect.

OR

Differentiate between a glass slab and a glass prism. What happens when a narrow beam of (i) a monochromatic light, and (ii) white light passes through

(a) Glass slab

(b) Glass prism