Which term is used for polymers made up of a large number of glucose units?

Cellulose

The correct answer is option 3. Cellulose.

Cellulose is a complex carbohydrate and a natural polymer made up of a large number of glucose units linked together. It is one of the most abundant organic compounds on Earth and is a major component of the cell walls of plants. The structural arrangement of glucose molecules in cellulose differs from that in starch or glycogen, resulting in a linear and rigid polymer. Here is a more detailed explanation:

1. Glucose Units: Cellulose is composed of repeating units of glucose, which are linked together through β-1,4-glycosidic bonds. The glucose molecules are connected in a linear chain, forming long and straight cellulose polymers.

2. Plant Cell Walls:  In plants, cellulose plays a crucial role in providing structural support to cells. It forms a network of fibers within the cell walls, contributing to the rigidity and strength of plant tissues. The arrangement of cellulose fibers allows for a sturdy framework that maintains the structural integrity of plant cells.

3. Digestibility: While animals, including humans, lack the enzymes necessary to break down cellulose directly, some herbivores have specialized digestive systems or symbiotic microorganisms that can break it down into simpler sugars. Cellulose is an important dietary component for these animals.

4. Commercial Uses: Cellulose is also widely used in various industrial applications. It is a key component in the production of paper and cardboard. Additionally, cellulose derivatives are used in the manufacturing of textiles, films, and other products.

In summary, cellulose is a natural polymer consisting of glucose units and plays a critical role in the structural integrity of plant cells, as well as in numerous industrial applications.