Question

Pyrenoids are made up of
A) Core of starch surrounded by sheath of protein
B) Proteinaceous centre and starchy health
C) Core of protein surrounded by fatty sheath
D) Core of nucleic acid surrounded by protein sheath

Answer 1

Hint:Pyrenoids are subcellular microcompartments that are found in the chloroplasts. They appear to be a circular granular structure under a microscope.

Complete answer:
Pyrenoids form the dense bodies that are located in the chloroplast of the alga. They have the presence of certain layers around them which helps in storage of materials in the. Let us analyze the options in order to understand what pyrenoids are made up of.
>Option A: The core present in pyrenoids is composed of protein and not starch.Therefore, this is the incorrect option.
>Option B:Pyrenoids consists of a core that is proteinaceous in nature and a sheath of starch surrounding it. Therefore, this is the correct option.
>Option C: Pyrenoids are usually surrounded by layers of starch around them. No fatty sheath is found in pyrenoids.Therefore, this is the incorrect option.
>Option D: nucleic acids do not form the part of pyrenoid structure. Protein is found in the core of pyrenoids in the sheath.Therefore, this is the incorrect option.

Thus, the correct answer is option (B) Proteinaceous centre and starchy health.

Additional information:
-Pyrenoids was first described by Vaucher in 1803.
-It acts as a centre for carbon dioxide fixation, maintaining photosynthetic environment for RuBisCo

Note:Pyrenoids are involved in storage of starch for the alga and that is why layers of starch is found around them. They are also associated with carbon concentrating methods.