Standard 11|Plant Kingdom | Rhodophyceae | Short Note For NEET BIOLOGY

 

Chapter 3: Plant kingdom

Plant Kingdom |Rhodophyceae| Short Note For NEET BIOLOGY| standard 11

Note 5

Three types of algae- 

1. Chlorophyceae – green algae

2. Pheophyceae – brown algae

3. Rhodophyceae – red algae

Rhodophyceae - Red algae

Pigment :

––> r-phycoerythrin - a type of phycobillins (gives red color)

––>Chlorophyll a and d (for photosynthesis)

Habitat

––>Mostly marine

——> more available in warmer marine area

––> occur in area close to water surface - well lighted regions

––> also occur in great depths of ocean - relatively very low light

Structure:

––> multicellular thallus

––> some also have complex body organization (more developed than other type of algae)

——> Polysiphonia - very advanced red algae (extra information)

Storage food:

Floridian starch - very similar with amylopectin and glycogen

––>Monomer of Floridian starch also called as 'semi-amylopectin' (extra information)

Cell wall:

––>Cellulose

––>Pectin

––>Polysulphate esters

Reproduction:

Vegetative reproduction: fragmentation

Asexual reproduction: by non-motile spores

Sexual reproduction:

––> Oogamous

––>by non-motile gametes

––>complex post fertilization development - required because the algae itself has a complex structure (compared to other algae) - hence simple fertilization development won't help- more complex process needed

Examples:

––> Polysiphonia- advanced (complex) red alage

––>Porphyra - used in soups etc for flavor enhancement

––> Gracilaria - produce hydrocolloids- carageen

––> Gelidium - produce hydrocolloids- carageen

Happy learning!

Thank you for reading!

Manish Mevada

Urvi Bhanushali