Question

Macrocystis is a:
A) Red algae
B) Fungi
C) Bryophytes
D) Brown algae

Answer 1

Hint:Protista is a kingdom which consists of single celled eukaryotic organisms. Macrocystis is a type of multicellular plant like protist. They are mostly seen in temperate and subtropical areas.

Complete answer:
Let's analyse through the options for finding a correct answer.

Option A: Red algaes are one of the major and oldest groups of eukaryotic algaes. They are mostly seen in marine environments and relatively rare in freshwater environments. Red algae are also known as Rhodophytes. Floridean starch is the reserved food in red algae. Macrocystis do not belong to red algae. Therefore, this is the incorrect option.

Option B: Fungi are organisms which are classified as a kingdom, separating from other eukaryotic kingdoms such as plantae and animalia. They are heterotrophic organisms, which are also the major decomposers of nature. Macrocystis is not a member of fungi. Therefore, this is the incorrect option.

Option C: Bryophytes are a type of plant group, which are characteristically limited in size. Bryophytes are mostly seen in moisture areas. Macrocystis are not a member of this group. Therefore, this is the incorrect option.

Option D: Brown algae, also known as phaeophyceae, comprise a large group of multicellular algae. Brown algae are mostly seen in marine environments and they act as a source of food. Many of the species of brown algaes, which form great masses, contain high levels of biodiversity. Macrocystis belong to this group of algae.

The genus of Macrocystis contains the largest of all the phaeophyceae. This genus is found mainly at subtropical and temperate areas of the southern hemisphere. Macrocystis are one of the major components of kelp forests. Sargassum and fucales are some of the other examples of brown algae. Thus, this is the correct option.

Thus, the correct answer is option (D) Brown algae.
Note:Some of the brown algae, including macrocystis contain special gas filled bladder called pneumatocysts. They provide buoyancy to algae and help to keep the part of algae on the surface of water.