Final answer:
The reflex where an infant turns their head toward anything that touches their cheek is called the rooting reflex, which, along with the sucking reflex, is vital for feeding and survival.
Step-by-step explanation:
The reflex that Mary's infant daughter exhibits when her cheek brushes against her mother's blouse and she turns her head towards the chest is known as the rooting reflex. This is a newborn reflex where infants automatically turn their head toward anything that strokes their cheek or mouth, in preparation for feeding. This is one of several reflexes that are important for an infant's survival, as it helps to ensure successful breastfeeding.
The rooting reflex is accompanied by the sucking reflex, where newborns instinctively start to suck when a nipple is placed in their mouth, facilitating the intake of milk. Reflexes such as the Moro reflex and the grasping reflex are also essential for a newborn's initial months of development, offering mechanisms for the baby to instinctively react to stimuli that support feeding, protection, and physical bonding with the caregiver.