Algae is a highly diverse class of organisms having an ability to adapt and grow in a variety of ecosystems. They are generally aquatic organisms that have the ability to synthesize their own food. Although they conduct photosynthesis, they are not the plants in a true sense. Excessive growth of algae is an unhealthy sign because they can destroy the taste and nutritional value of the food, baking items, and many drinks. There are approximately 7000 species growing in a variety of habitats across the world. Algae has a mix of traits that make them diverse. The word algae- plural form of alga resembles some plants as well as another genus. However, very few varieties of algae such as seaweeds are more familiar to the general population.  “Algae is a term that describes a large and incredibly diverse group of eukaryotic, photosynthetic life forms. These organisms do not share a common ancestor hence, they are not related to each other (polyphyletic).” Most of the simpler algae are unicellular flagellates or amoeboids, but colonial and nonmotile forms have developed independently among several of the groups. Algae has a wide morphological variations within  themselves. Colonial algae are charcacterised by being  small, regular groups of motile cells. Capsoid  ones are individual non-motile cells embedded in mucilage . Coccoid type of algae  are individual non-motile cells with cell walls. Palmelloid are also  nonmotile cells embedded along with the mucilage. Filamentous ones have a string of nonmotile cells connected together with or without branching.Parenchymatous  are the cells forming a thallus with partial differentiation of tissues.


Table Of Contents

1. Introduction

2. Characteristic features of algae

3. Classification of Algae

4. Importance of algae



Characteristic features of algae

  1. One of the unique differences between the plants and algae is that they lack typical roots, stems, leaves, and a proper vascular system to circulate water and nutrients throughout their bodies but they can still participate in photosynthesis.

  2. Another surprise and astonishing fact is that algae encompasses innumerable species ranging from a single-celled alga to giant kelps measuring as lengthy as 60 meters.

  3. They breed in a range of aquatic habitats that are of both the freshwater and saltwater.

  4. Algae can be called both prokaryotic organisms (like cyanobacteria) also eukaryotic organisms such as blue-green algae.

  5. Algae has an ability to photosynthesize like plants, as they possess the necessary photosynthetic organelles. While most algae are photoautotrophs (as they use light energy to generate nutrients).

  6. Algae can be either unicellular or multicellular.

  7. Reproduction in algae occurs in both asexual and sexual modes. Asexual reproduction occurs by spore formation.

  8. Algae are free-living, although some can form a symbiotic relationship with other organisms.


Classification of Algae

Although Algae is classified in many ways as shown in the chart below, the main classification is based on colour -the presence of pigments. 3 major types of algae are Chlorophyceae, Phaeophyceae, and Rhodophyceae.

  1. Chlorophyceae is also known as green algae, due to the presence of pigments and chlorophyll a and b. Examples are Chlamydomonas and Spirogyra,

  2. Phaeophyceae are also known as brown algae live in the marine ecosystem. They have chlorophyll- a, and c, carotenoids and xanthophyll pigments. For example, Dictyota, Laminaria, and Sargassum.

  3.  They are the red algae as they have red pigment. For example, Porphyra, Gracilaria, and Gelidium.



Importance of Algae

Algae is one of the favourites within the food industry, however, they are also useful as fodder, pisciculture, fertilizer, and in some chemical reactions. Some of the uses are as under

  1. Food industry: They are the rich source and can be made use as a complete balanced menu containing carbohydrates, fats, proteins, and vitamins A, B, C, and E. Micronutrients like iron, potassium, magnesium, calcium, manganese, and zinc. In many countries, algae have been used as a supplement in the form of powder and snacks. However, there seems to be a risk of food poisoning if the food packing and processing are poorly done.

  2. Fertilizer: Algae are rich in minerals and vitamins. So they also used as liquid fertilizer which helps in the repairing level of nitrogen present in the soil.

  3. Reclaiming Alkaline: Blue-Green Algae helps in the reduction of a high concentration of alkalinity in the soil.

  4. Binding Agent: Algae act as the binding agents against natural processes such as erosion.

  5. Biological indicator: Algae are very sensitive. If there is a slight change in the environment their pigments changes or might get died.  Water pollution is checked with the help of Algae like Euglena and Chlorella.

  6. Fodder: To feed livestock such as cattle and chickens, algae is preferred.

  7. Pisciculture: In fish farming, Algae plays a very important role because it helps in the production process. Fish used plankton and zooplankton as food. It helps in maintaining the health of the marine ecosystem because algae are naturally absorbent of carbon dioxide and also provide oxygen to the water.




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