The soft spots on an infant's skull where sutures have not yet fused are called:

• A. Fontanelles
• B. Sutures
• C. Cranial Valleys
• D. Ventricles

Answer: (A)

Fontanelles are the soft spots on an infant's skull where the bones have not yet fused. They’re membranous gaps between the developing skull bones that allow the head to mold during birth and to expand as the brain grows in the first years of life. There are two main fontanelles—the anterior one on top of the head and the posterior one toward the back. The posterior fontanelle closes earlier, by about 2–3 months, while the anterior fontanelle stays open longer, typically until about 12–18 months (sometimes a bit longer). Clinically, you can feel these spots to gauge hydration and potential intracranial issues: a bulging fontanelle may indicate increased pressure or crying, whereas a sunken fontanelle can suggest dehydration. The other terms don’t describe these soft spots—sutures are the joints between skull bones, ventricles are brain cavities, and “cranial valleys” isn’t a standard term.