Question

monosaccharides are the building blocks of carbohydrates. they may be found alone or combined with other molecules in fruits, vegetables, dairy products, and grains. the model shows the chemical structures of three monosaccharides: glucose, fructose, and galactose. compare glucose, fructose, and galactose. select the true statements. glucose, fructose, and galactose are monosaccharides. all three molecules have six carbon atoms. fructose has a six-atom ring. only galactose has oxygen atoms.

Explanation:

1. For the statement "Glucose, fructose, and galactose are monosaccharides": The problem states monosaccharides are building blocks of carbohydrates and the model shows these three as monosaccharides, so this is true.
2. For the statement "All three molecules have six carbon atoms": The chemical formulas (e.g., \(C_6H_{12}O_6\) for glucose and galactose, same for fructose) show 6 carbon atoms, so this is true.
3. For the statement "Fructose has a six - atom ring": Looking at the fructose structure, its ring has 5 atoms (4 carbons and 1 oxygen), so this is false.
4. For the statement "Only galactose has oxygen atoms": All three (glucose, fructose, galactose) have oxygen in their structures (e.g., \(OH\) groups, ring oxygen), so this is false.

Answer:

• Glucose, fructose, and galactose are monosaccharides.
• All three molecules have six carbon atoms.