Lloyd A. Hause
Colorado Technical University
Professor Darlene Perdue
From infancy to adolescence many anatomical and physiological changes will occur, often in stages. From the moment a newborn leaves the womb and takes its first breath of air, a rollercoaster of events is set into motion. This is also the time that the new infant is most vulnerable to injury and infection. This is primarily due to the fact that not all of the infant’s body systems and parts are fully mature yet. For instance, the epidermis is very fragile and can be torn easily; the kidney, liver, neurological system, and immunological system are not developed to full capacity. Over a period of days, weeks and years and infant slowly matures and continues to grow and go through stages of change until adulthood.
Growth and development of a child occurs more rapidly during infancy. During the first year of infancy, especially the first six months of life, is when the body changes rapidly. It is expected that a baby will gain 1.5 pounds per month for about the first five to six months of its life. At the same time, the infant is growing in height at a rate of around one inch per month. As stated by Wong, “Infants gain 680g (1.5 pounds) per month until age 5 months, when the birth weight has at least doubled.” and “Height increases by 2.5cm (1 inch) per month during the first 6 months and by half that amount per month during the second 6 months.” (Hockenberry & Wilson, 2007) After this first year of life, a child continues to grow and develop, just at a slower rate, until early adolescence, which is around 11-14 years of age. Then once again the body begins to go thorough more rapid changes, such as rapid physical growth. From birth to adolescence, many anatomical and physiological changes occur. Skeletal and muscular growth of a human being is probably one of the most noticeable changes throughout the different stages of life. As mentioned, an infant nearly doubles its birth weight by month five as well as doubling in height by month six. At birth, a newborn’s skeletal system primarily consists of cartilage rather than bone. For instance, the nose is mainly cartilage and is often flattened by delivery. The skull is another example, at birth the skull bones are still soft and not sutured yet. The cranial sutures usually begin to close around six to eight weeks of life. By the end of a baby’s first year, their head size has increased nearly 33%. (Hockenberry & Wilson, 2007) During preadolescence, there is another rapid acceleration of growth. This is the time period that a person reaches their peak heights, 20% to 25% of height and nearly 50% of adult weight is achieved during this time. (Hockenberry & Wilson, 2007) Once difference, between infants and adolescents is the time frame that their height and weight gains occur. An infant achieves approximately the same height and weight gain during their first six months of life, regardless of sex. Whereas, preadolescents around the ages of eleven to fourteen gain height and weight at different ages, depending on the whether they are male or female. Females start their growth spurt around the age of twelve where boys start around the age of fourteen. As stated by Perry & Potter, “For girls, height increases 2 to 8 inches and weight increases by 15 to 55 pounds. Height for boys increases approximately 4 to 12 inches, and weight increases by 15 to 65 pounds.” (Potter & Perry, 2009) Girls also typically achieve their adult maximum height before menstruation begins, normally before age fourteen. Males on the other hand, continue to grow taller until about the age of eighteen or twenty. Another growth difference between infants and adolescence is where on the body the growth is most significant. With infants the growth occurs mainly in the trunk, instead of the extremities. With adolescents, growth...