Question

The largest alga is
A. Microcystic
B. Macrocystis
C. Red alga
D. Blue-green alga

Answer 1

Hint: The largest alga is not really a plant, and it has no roots. Instead it gets all the essential nutrients straight from the water and is bound by a device known as a holdfast to the rocky bottom

Complete Answer:
Algae are a diverse group of marine species which can undergo photosynthesis. For most people, some algae are familiar; for example, seaweed, such as kelp or phytoplankton, pond scum, or lake algal blooms. There is, however, a vast and complex ecosystem of algae that is not only beneficial to us but vital to our life.

 Now, let us find the solution from the option.
1) Microcystic algae are found in freshwater.
2) Macrocystis is the greater type of algae.
- Macrocystis is a genus of big brown algae or kelp. It is present in the Pacific Ocean’s cold coastal waters and portions of the southern Atlantic Oceans.
-This class includes the majority of all the brown algae called Phaeophyceae.
- It has pneumatocysts at its blade base.
3) Sporophytes are permanent and can persist with single stripes for several years. It is widespread along the eastern Pacific coast.
- The kelp harvests the energy of the light through photosynthesis, and does not depend on other species.
4) In freshwater habitats with higher concentrations in colder areas, red algae exist.

Thus, the correct option is (B) Macrocystis.

Note: When the individual kelp hits the surface of the sea, it begins to expand horizontally, spreading in large mats covering the column of water and the seabed below. To keep upright, the kelp blade (leaf) contains a gaseous pod that floats.