NUTRITION OF ALGAE

 NUTRITION OF ALGAE

·    Majority of the Algae are Photoautotrophic in nature. They synthesize their food from inorganic materials such as carbon dioxide, water and minerals by means of Photosynthesis.

·       The mode of nutrition in Algae is primarily of three types, namely

a)     Photoautotrophic algae - Undergo Photosynthesis to synthesize their food.

b)     Heterotrophic algae - Utilize Organic nitrogen or carbon sources and nutrients in soil or water to synthesize essential oils, fats and proteins.

c)     Mixotrophic algae - Utilize both Organic and Inorganic sources to fulfil their growth and nutritional needs.

·       On the basis of their nutritional strategies, Algae are into classified four groups:

a)     Obligate Phototrophic Algae

ü  Obtain nutrition by utilizing Inorganic sources like CO₂, H₂O and Sunlight or through Photosynthesis.

ü  In case of limited Sunlight, Obligate Phototrophic Algae sustain life through Phagotrophy (engulfment of large food particulate inside cells) or Osmotrophy (feeding mechanism involving the movement of dissolved organic compounds by osmosis for nutrition).

ü  Examples: Dinobryon divergons, Heterokontophyta, etc.

b)     Obligate Heterotrophic Algae

ü  Obtain nutrition by a heterotrophic mode. In conditions of limited Heterotrophy, they sustain themselves by undergoing Phototrophy (utilization of solar electromagnetic radiation for energy conservation).

ü  Examples: Dinophyta, Gymnodium gracilentum, etc.

c)      Facultative Mixotrophic Algae

ü  Obtain nutrition through Photoautotrophy as well as Heterotrophy.

ü  Example: Dinophyta

d)     Obligate Mixotrophic Algae

ü  Obtain nutrition through Photoautotrophy and need B -complex Vitamins, Amino acids and Fatty acids for growth.

ü  Examples: Euglena gracilis, Euglenophyta, etc.