Question

Algae have cells made up of
(a)Cellulose, galactans, and mannans
(b)Hemicellulose, pectins, and proteins
(c)Pectins, cellulose, and proteins
(d)Cellulose, hemicelluloses, and pectins

Answer 1

Hint: Algae have cells that are made up of various polysaccharides. In order to manufacture paperboard and paper, one polysaccharide is primarily used. The agars and carrageenans reflect a polysaccharide found in algae. The other polysaccharide is a type of polysaccharide for storage.

Complete answer:
Alga is a term describing a wide and unbelievably complex community of types of eukaryotic, photosynthetic existence.
Algae have cell walls that include either polysaccharides such as cellulose (a glucan) or a number of glycoproteins, or both, much like plants. The algae have a cell wall composed of cellulose, mannans, and galactans.
The primary cell wall of green plants, several types of algae, and oomycetes are essential structural components of cellulose.
A polysaccharide composed of polymerized galactose is galactan (galactosan).
As a method for algal taxonomy, the presence of additional polysaccharides in algal cell walls is also used. In the cell walls of a number of marine green algae such as those in the genera Codium, Acetabularia, and in the walls of some red algae such as Porphyra, mananas sort of microfibrils exist.

Additional Information: -Cellulose comes from D-glucose units that condense via glycosidic bonds of $\beta \left(1\to 4\right)$.
-Mannan may refer to a plant polysaccharide that is a sugar mannose linear polymer. Plant mannans have linkages of $\beta \left(1\to 4\right)$. It is a type of polysaccharide for storage. Ivory nuts are a source of mannan. Mannans are a collection of heterogeneous glycans that are prevalent among green algae and earthly plants.
-In general, galactans contain a core of galactose units linked by $\alpha \left(1\to 3\right)$ or $\alpha \left(1\to 6\right)$ in natural sources, with structures containing other monosaccharides as side-chains.
So, the correct answer is, ‘Cellulose, galactans, and mannans’.

Note: -Galactans are found in red algae and are commercially important because of their rheological properties due to their widespread use as gelling and thickening agents in the food industry. Such galactans are essentially known as agarans and carrageenans, based on their stereochemistry.