The following factors are worth understanding regarding early child development.
During early child development, as the child grows in size, the rate of growth of different parts of the body differs from one another. Development of head takes place first followed by the development of lower parts of the body during the prenatal (in the womb) stage of development. During infancy and childhood, head, chest and trunk grow first, followed by the growth of arms and legs and finally the growth of hands and feet. During adolescence, the growth pattern is in the reverse direction. There is acceleration in the growth of arms, legs, hands and feet first and then the trunk grows. Because of this pattern of growth the adolescent gains height.
Human nervous system consists of two major parts - Central nervous system and Peripheral nervous system. The Central nervous system consists of the brain and the spinal cord. The brain is made up of a large number of brain cells. These brain cells are connected among themselves through nerve fibres, thereby forming a network of connections. As part of early child development, the development of the brain is not complete at birth. A baby's brain consists of nearly 100 billion brain cells at birth. Most of the cells of the brain are formed before birth but connections among the cells are mostly made during infancy and early childhood, except for the early connections which regulate heartbeat, respiration and reflexes. The child's early experiences and interaction with the environment allows for later connections to be made between nerve cells and thus the brain develops. The development of the baby's brain is so fast that by two years of age the baby has as much connections as that of an adult. By age three, the child's brain is twice as active as an adult's brain. Nature and nurture provides for good development of the child's brain. Good nutrition even before the baby is born and afterwards plays an essential role in brain development. Also, loving care and attention by care-givers help in good brain development.
All the five sense organs are present at birth but are not well developed and therefore not completely functional at birth. Only after two to three months, the child can see things clearly. Baby's hearing is clear only several days after birth. The skin is thinner than that of an adult, so the baby can feel touch, pain and temperature more acutely than an adult. The baby has a keen sense of smell, more than that of an adult because there are no hairs on the inside of the nostrils as in an adult and smell reaches the smell cells easily. The baby is very sensitive to all tastes because there are taste buds on the inside of the cheeks too in addition to the normal taste buds on the surface of the tongue as found in adults.
Physical maturity of a child is determined by the growth of bones. Bones of the newborn infant are soft, more like cartilage [soft bone tissue] than like hard bones.Though the bones of an infant are generally soft, they are softest on the top middle portion of the head.These soft bones begin to harden slowly through the infant stage, the softest bones on the top portion of the head becomes well hardened by two years. Hardening of bones continues up to the beginning of adolescent stage. Lengthening of bones determines the height of a child. Bones tend to grow longer because of the presence of the thin layer of cartilage near the ends of the bones. Growth in length of bones takes place in a process where the cartilage cells divide and multiply and get converted into bones. This process continues throughout childhood and during further physical growth cartilage cells get thinner and disappear. Once this happens growth in bone length comes to an end. Children are born with 270 bones. Calcium helps in building up of bones, maintaining them and making them strong. Calcium rich food and regular exercise are important to keep bones healthy. Calcium rich food are milk, cheese, yogurt and greens.
The baby's teeth are a set of temporary teeth. They are 20 in number and known as milk teeth or the primary teeth. They are usually soft and small with shallow roots. Teeth start to develop during the prenatal stage itself. At birth, the child has all the primary teeth present, hidden within the gums. The eruption of teeth out from within the gums is known as teething or cutting teeth. A child cuts his first tooth around six months of age. Then teeth continue to appear at the rate of one tooth per month. There are however variations in the timing of cutting the first tooth. In some the first tooth appears when the baby is only a few months old and in others it may take even 12 months or more to cut the first tooth. Though the time of cutting teeth varies, teeth appear in the same order in all children, except in rare cases where the teeth do not appear in sequence. The first teeth to appear are the two front teeth of the lower jaw which occurs when the baby is 6 to 10 months old. Next teeth to appear are the two front teeth of the upper jaw. This occurs between 8 and 13 months. The front teeth are called incisors. The lower and upper side teeth called the lateral incisors appear between 8 and 16 months. Then appear the first set of molars [back teeth], canines beside the lateral incisors and the second set of molars. By the age of 2.5 to 3 years an average child has the full set of primary teeth. Between 6 and 7 years the primary teeth begin to shed and the first permanent teeth begin to appear. A baby experiences pain even a month or two before he cuts the first tooth. The diet should be good at infant and childhood stage, so that the temporary milk teeth survive without any tooth decay until they are replaced by a permanent set of 32 teeth.