Algae are the simplest
kinds of plants. They contain chlorophyll; therefore, they can make their food
by photosynthesis. They lack vascular bundles, i.e. they do not posses xylem
and phloem. Their thallus lacks true roots, shoots and leaves algae include
unicellular plants to very big multicellular plants. They do not form embryo
after sexual reproduction. Commonly, algae are colored and they can grow up to
40 or 60 meters in length.
Most algae grow in rivers, ponds, lakes and oceans. Some
can live in moist places on land, mountains and near trees. A few species of
algae are found on the ice in the Polar Regions
and in hot water springs. Some of the blue- green algae can survive even at
70-80 degree centigrade. Some algae grow on plants and a few complete their
life cycle inside some plants. Many algae are saprophytic and parasitic. The
best known algae are probably the seaweed found at beaches.
About 25-30 species of algae are used as food by man. The
algae porphyra of phiopcae class is a common meal in Japan. In china, Nostoc commune is
used as food. In India,
algae are used to prepare ice-cream, chocolate milk, gelatin and beer. Some
algae are poisonous in nature and can paralyze a person.
We get carbohydrate, vitamins A, B, C, D, E and other
materials from algae. Fish depend on algae for their food. Many algae obtained
from oceans are rich sources of iodine, potassium and other minerals. Algae are
a good fertilizer also. The red algae grow in large colonies and turn the water
red. Some red algae also form islands.
Different species of algae
No comments:
Post a Comment