Question

Examine the figure given below and select the right option giving all the three parts (A, B and C) correctly identified/characterized.

• A. A - $N_2$ fixation, B - Mucilaginous sheath, C - Akinete
• B. A - Carbon fixation, B - Gelatinous sheath, C - Lack PS-II
• C. A - Both PS-I and PS-II, B - Mucilaginous C - Anoxygenic photosynthesis
• D. A - Vegetative cell, B - Cell wall, C - Carbon fixation

Answer 1

Answer: (A)

A - $N_2$ fixation, B - Mucilaginous sheath, C - Akinete

A. A - $N_2$ fixation, B - Mucilaginous sheath, C - Akinete

Solution: Heterotrophic bacteria live in the soil and fix significant levels of nitrogen without direct interaction with other organisms. An akinete is a thick-walled dormant cell. It is formed by filamentous, heterocyst-forming cyanobacteria under the order nostocales and stigonematales serves as a survival structure. It is a resting cell of cyanobacteria and unicellular and filamentous green algae. Mucilage is a thick, gluey substance produced by nearly all plants and some microorganisms.

So, the correct answer is option A.