Storage bodies,pyrenoids in the chloroplast contain

Read carefully the given statements about algae and choose the correct option.
$I$. The plant body is thalloid.
$II$. Mainly aquatic.
$III$. Reproduction takes place by vegetative,asexual,and sexual methods.
$IV$. Volvox and Ulothrix are the colonial forms of algae.

In $Spirogyra$,during the germination of the zygospore,how many haploid nuclei take part in the formation of a new filament?

Which is the correct statement for $Ulothrix$?

Which type of algae helps in the nitrogen economy?

Which of the following statements are applicable to brown algae?
$(I)$ They contain pigments like chlorophyll $a$,chlorophyll $c$,carotenoids,and xanthophylls.
$(II)$ They vary in color from olive green to various shades of brown.
$(III)$ Food is stored as complex carbohydrates,in the form of laminarin or mannitol.
$(IV)$ The cell wall is composed of cellulose and algin.
$(V)$ The cell wall is covered on the outside by a gelatinous coating of algin.