Question

Mitochondria are absent in
(a)Green algae
(b)Brown algae
(c)Blue-green algae
(d)Red algae

Answer 1

Hint: Mitochondria are one of the important membrane-bound organelles that are seen in eukaryotic cells. Mitochondria's main function is to help in the production of energy that is in the form of Adenosine Triphosphate (ATP).

Complete answer : Blue-green algae are prokaryotic bacteria, unlike other algae which are eukaryotic organisms and hence do not possess membrane-bound organelles such as mitochondria.

Additional information:
>The mitochondrion is the membrane-bound organelle found in the cytoplasm of nearly all eukaryotic cells.
>The principal function of mitochondria is to produce great quantities of energy in the form of adenosine triphosphate (ATP). The mitochondrion is hence known as the powerhouse of the cell.
>Along with producing energy, mitochondria store calcium used in cell signalling activities, produce heat, and help in controlling cell growth and death.
>Mitochondria are different from other cellular organelles in that they have two different membranes and a unique DNA that allows it to reproduce autonomously by binary fission.

So, the correct answer is “Blue-green algae”.

Notes:Cyanobacteria compared to other algae are more likely dangerous to the ecological environment of the aquatic organisms. This issue relates to the fact that they release certain toxins which are poisonous to other organisms including plants, insects, snails, etc. They are also harmful to other algae eating microorganisms called zooplankton and fish. Green algae on the other hand provide a source of food for the zooplankton to grow and flourish.