Final answer:
Infant bones are not fully ossified at birth and contain cartilage, leading to potential confusion with soft tissues. Ossification transforms cartilage into bone, but it's an ongoing process through childhood, leaving areas like the newborn skull soft and flexible.
Step-by-step explanation:
Infant bones are often confused with other types of tissue because they are different from adult bones. At birth, the skeleton of an infant is not fully ossified, which means that the bones are not completely hardened, and many are still partly made of cartilage. This cartilaginous state could lead to confusion with other soft tissues. The newborn skull, for example, has large areas called fontanelles that are filled with connective tissue to allow for the growth of the skull after birth. The process through which cartilage transforms into bone is known as ossification. Intramembranous ossification is responsible for the beginning of bone development in utero and continues through adolescence. However, not every part of the cartilage is replaced by bone; some remains in areas like joints, rib cages, and other parts of the body, contributing to the flexibility and growth potential of the infant's skeleton. The development of bones in infants involves the replacement of the cartilaginous matrix with bone during fetal development and throughout childhood. The growth plates at the ends of long bones, for example, consist of cartilage that persists throughout childhood, allowing the bones to lengthen as the child grows.