Write a note on Chlorophyceae.

(N/A) The members of Chlorophyceae are commonly called green algae.
Structure and characteristics:
- The plant body may be unicellular,colonial,or filamentous.
- They are usually grass green due to the dominance of pigments chlorophyll $a$ and $b$.
- The pigments are localized in definite chloroplasts. The chloroplasts may be discoid,plate-like,reticulate,cup-shaped,spiral,or ribbon-shaped in different species.
- Most of the members have one or more storage bodies called pyrenoids located in the chloroplasts. Pyrenoids contain protein besides starch.
- Green algae usually have a rigid cell wall made of an inner layer of cellulose and an outer layer of pectose.
Reproduction in green algae:
- Vegetative reproduction usually takes place by fragmentation or by the formation of different types of spores.
- Asexual reproduction is by flagellated zoospores produced in zoosporangia.
- Sexual reproduction shows considerable variation in the type and formation of sex cells and it may be isogamous,anisogamous,or oogamous.
- Examples: $Chlamydomonas$,$Volvox$,$Ulothrix$,$Spirogyra$,and $Chara$ are commonly found green algae.