That statement is incorrect. The sides of the DNA ladder are not made up of alternating sugar molecules and carbohydrate groups. Here's the correct breakdown:

* Sugar molecules (deoxyribose): These form the backbone of the DNA ladder. They are linked together by phosphate groups.

* Phosphate groups: These link the sugar molecules together, creating the two long strands that make up the sides of the DNA ladder.

* Nitrogenous bases: These are attached to the sugar molecules. They form the "rungs" of the DNA ladder, connecting the two strands. There are four types of nitrogenous bases: adenine (A), thymine (T), guanine (G), and cytosine (C).

So, the sides of the DNA ladder are made up of alternating sugar molecules (deoxyribose) and phosphate groups. Carbohydrate groups are not a primary component of the DNA backbone.