Which of the following produces isogamous and non-flagellated gametes?

In $Ulothrix$,the zygote is

In $Chlorophyceae$,sexual reproduction occurs by .............

Which of the following statements are true regarding the figure given below?
$(i)$ It shows oogamy and post-fertilization development.
$(ii)$ Male gamete is small and motile.
$(iii)$ Stored food is floridean starch.
$(iv)$ Pectin,cellulose,and polysulphate esters are present in the cell wall.

The chloroplast of $Chlamydomonas$ is . . . . . . .

Pyrenoids are typically found in algae. $A$ pyrenoid is made up of: