Carbohydrates are stored in the muscles and liver as:

Carbohydrates are stored in the muscles and liver as glycogen, which is a polysaccharide that serves as a form of energy reserve in humans and animals. Glycogen consists of many glucose molecules linked together, allowing for quick conversion back to glucose when energy is needed by the body. When you consume carbohydrates, your body can convert excess glucose into glycogen through a process called glycogenesis.

While glucose is indeed the simple sugar form of carbohydrates, it is not stored directly in the body; instead, it is the building block from which glycogen is synthesized. Starch is a form of carbohydrate storage found primarily in plants, and cellulose is a structural component of plant cell walls that humans cannot digest. Thus, glycogen is the correct term for the specific storage form utilized by the muscles and liver for maintaining energy levels.