Mannitol is the stored food in A. Gracilaria B. Chara C. Porphyra D. Fucus
Hint: Mannitol is a form of carbohydrate that is called sugar alcohol or polyol. Mannitol contains about 60 percent less calories than sugar and is half as sweet.
Complete Answer: - Mannitol is also commercially manufactured for use in chocolate coatings, confections, chewing gums, powders and tablets to provide body, sweetness, cooling taste and texture. It is also useful as an anti-caking agent because of its minimal ability to absorb water. - Fucus, also known as rockweed, a genus of brown algae, abundant on rocky coasts and in salt marshes of temperate northern regions. Fucus species are an important source of alginate-colloid extracts with many industrial uses comparable to agar extracts, along with other kelps. Plants consist of a thallus that is flattened, dichotomously-branched, which has a small stem and a fast grip. The blade usually has a locally thickened area called a midrib that is centrally located. - Fucus belongs to the Phaeophyceae class in which the food is preserved in the form of laminarin, mannitol and oil. - Chara belongs to class Chlorophyceae in which the food is stored in the form of starch and oil. - Porphyra and Gracilaria belong to the Rhodophyceae class, where food is stored in the form of polymers of Floridean starch and Galactan-So4.
Thus the correct answer is option(D) Fucus.
Note: Mannitol is the primary component in mannitol salt agar, a bacterial growth medium, and is used in others.Brown algae, including kelp beds, also fix a significant portion of the earth's carbon dioxide annually through photosynthesis. And they can store a large amount of carbon dioxide in them that can help us in the fight against climate change.