Final answer:
During infancy, physical developments include motor skills, sensory abilities, and cognitive abilities. Vision is not fully developed in newborns and reflexes like suckling and rooting help them survive. The timing of developmental milestones may vary among infants, but the general sequence is similar.
Step-by-step explanation:
During infancy, several types of physical developments occur. These include motor skills, sensory abilities, and cognitive abilities. Motor development in infants progresses from reflexive reactions to advanced motor functioning such as sitting unassisted, crawling, and walking. Sensory abilities in newborns include touch, hearing, taste, and smell, but their vision is not fully developed. Infants are born with reflexes like suckling and rooting, which help them survive. The timing of developmental milestones, such as sitting and walking, may vary slightly among infants, but the general sequence is similar.