Question

Cyanophyceae (Blue-Green Algae) belongs to
A. Plantae
B. Protista
C. Monera
D. Metaphytea

Answer 1

Hint: Blue-green algae also called cyanobacteria are primitive algae. They belong to a kingdom that consists of unicellular prokaryotic organisms. These are usually green in color due to the presence of chlorophyll. They are autotrophic prokaryotes.

Complete answer: Cyanophyceae are a group of primitive algae which are commonly called Blue-green algae. These are green in color due to the presence of a green pigment called chlorophyll. Due to the presence of chlorophyll, they are able to perform photosynthesis. Thus, these are the simplest autotrophic prokaryotic organisms. These are prokaryotes which means that they have no true nuclear membrane around their genetic material.
Cyanophyceae belongs to the Monera kingdom which includes unicellular prokaryotic organisms. Cyanobacteria have an absence of well-organized cell organelles and different pigments are present throughout the chromoplasm. The chromoplasm is the outer part of the protoplasm of cyanobacteria. The Cyanophyceae are called Blue-green algae due to their resemblance to algal cells. But these are not algae and sometimes are considered primitive algae. Cyanobacteria are non-flagellated cells and their cell walls are made of mucopeptide. They generally lack locomotion. They reserve their food in the form of cyanophycean starch and granules. The blue cyanobacteria have c-phycocyanin as their key pigment and the red cyanobacteria have c-phycoerythrin as their main pigment.
So, we can conclude that option C is correct.

Note: As cyanobacteria have chlorophyll pigment in them scattered in not well-organized thylakoids of the chloroplast, these are thought to be primitive algae. Also, it is thought that once cyanobacteria cell was associated with the plant cell and this resulted in a typical plant cell having chlorophyll. Cyanobacteria also contribute to some portion of oxygen on Earth.