Which one of the following shows isogamy with non-flagellated gametes?

What does $''Y''$ represent in the given chart?

Describe the types of reproduction in red algae (Rhodophyceae).

Which of the following is incorrectly matched?

Select the correct option from the given list regarding algal classes and their stored food materials:
$(1)$ Rhodophyceae - Pyrenoids
$(2)$ Phaeophyceae - Laminarin
$(3)$ Bryophytes - Mannitol
$(4)$ Chlorophyceae - Floridean starch

Which of the following pairs is $NOT$ correctly matched?