**Core Concept**
Glucose is a monosaccharide, a simple sugar that serves as a fundamental building block of more complex carbohydrates. As a monosaccharide, glucose has a specific chemical structure that distinguishes it from other sugars.

**Why the Correct Answer is Right**
Glucose is indeed a key component of the disaccharide sucrose, also known as table sugar. Sucrose is formed through the condensation reaction of glucose and fructose molecules, resulting in a disaccharide with a glycosidic bond. This bond links the two sugar molecules together, creating a new compound with distinct properties. The correct answer highlights glucose's role in forming this important disaccharide.

**Why Each Wrong Option is Incorrect**
**Option A:** Glucose typically exists in the pyranose form, not the furanose form, due to its six-membered ring structure. This is a crucial distinction in carbohydrate chemistry.
**Option B:** Glucose is actually an aldose, not a ketose, as it contains an aldehyde functional group at its open end. This classification is vital for understanding glucose's chemical properties and behavior.
**Option C:** Glucose does not possess an anomeric C-2 carbon atom; instead, it has an anomeric carbon atom at position C-1, which is involved in forming glycosidic bonds with other sugar molecules.

**Clinical Pearl / High-Yield Fact**
Glucose is a vital energy source for cells, particularly neurons, which rely heavily on glucose for their metabolic needs. In diabetes mellitus, impaired glucose metabolism can lead to severe complications, including neuropathy and cognitive decline.

**✓ Correct Answer: D. It forms part of the disaccharide sucrose**