Реферат: Influences On Normal Physical Essay Research Paper
Influences On Normal Physical Essay, Research Paper
Physical growth in early childhood is partially easy to measure and
gives an idea of how children normally develop during this period. The
average child in North America is less than three feet tall at two years of
age. Physical growth contains no discrete stages, plateaus, or qualitative
changes. Large differences may develop between individual children and
among groups of children. Sometimes these differences affect the
psychological development of young children. These differences create a
nice variety among children.
Most dimensions of growth are influenced by the child’s genetic
background. Also, races and ethnic backgrounds around the world differ
in growth patterns. Nutrition can affect growth, but it does not override
genetic factors.
One factor in the cause of slow growth is malnutrition. Malnutrition
can start as early as pregnancy. Low birth weight babies have an
increased risk of infection and death during the first few weeks of life.
Food-deprived children carry a greater risk of neurological deficiencies
that result in poor vision, impaired educational attainment, and cerebral
problems. Such children are also more prone to diseases such as malaria,
respiratory tract infections or pneumonia. The illnesses of malnourished
children can cause more lasting damage than in a healthy child. The
destructive conjunction between low food intake and disease is magnified
at the level of the hungry child. There is evidence, according to The
Journal of Nutrition, that an estimated 50 percent of disease-related
mortality among infants could be avoided if infant malnutrition were
eradicated. It has also been shown that low birth- weight is associated
with increased prevalence of diseases such as stroke, heart disease and
diabetes in adult life. Most damage during the first few years of life
cannot easily be undone.
There are many reasons why some children never reach normal
height. Some causes of short stature are well understood and can be
corrected, but most are subjects of ongoing research. Achondroplasia is
the most common growth defect in which abnormal body proportions are
present. Achondroplasia is a genetic disorder of bone growth. It affects
about one in every 26,000 births. It occurs in all races and in both
sexes. It is one of the oldest recorded birth defects found as far back as
Egyptian art. A child with achondroplasia has a relatively normal torso
but short arms and legs. People sometimes think the child is mentally
retarded because they are slow to sit, stand, and walk alone. In most
cases, however, a child with achondroplasia has normal intelligence.
Children with achondroplasia occasionally die suddenly in infancy or early
childhood. These deaths usually occur during sleep and are thought to
result from compression of the upper end of the spinal cord, which can
interfere with breathing. This disease is caused by an abnormal gene.
The discovery of the gene allowed the development of highly accurate
prenatal tests that can diagnose or rule out achondroplasia. There is
currently no way to normalize skeletal development of children with
achondroplasia, so there is no cure. Growth hormone treatments, which
increase height in some forms of short stature, do not substantially
increase the height of children with achondroplasia. There is no way to
prevent the majority of cases of achondroplasia, since these births result
from totally unexpected gene mutations in unaffected parents.
One treatment available for children is known as growth hormone
therapy. The policy governing the use of growth hormone (GH) therapy
has shifted from treating only those children with classic growth hormone
deficiency to treating short children to improve their psycho social
functioning. This has caused quite a controversy. Parents have described
shorter boys as less socially competent and having more behavioral
problems than that of the normal sample. Shorter boys describe
themselves as less socially active but not having more behavioral
problems than that of the normal group. This is according to a study
conducted by the Children’s Hospital of Buffalo and the State University
of New York at Buffalo. The researchers conclude growth hormone
therapy should not be administered routinely to all short children for the
purpose of improving their psychological health. They urge that
physicians consider both a child’s short stature and psycho social
functioning before making a referral for growth hormone therapy.
Another factor in the growth of children is their change of appetite.
Young preschoolers may eat less than they did as a toddler. This is also
when they will become more selective and choosy with the foods they
eat. These changes are normal and result from the slowing down of
growth after infancy. Preschool children simply do not need as many
calories as they did after birth. Children’s food preferences are influenced
by the adult models around them. Preschoolers tend to like the same
foods as their parents and other important adults in their lives.
Variations in growth can result from cultural and psychological
factors. Failure to thrive is defined in the class textbook as a condition in
which an infant seems seriously delayed in physical growth and is
noticeably apathetic in behavior. This condition may result from situations
that interfere with normal positive relationships between parent and child,
especially during infancy or the early preschool period. The result is a
deprived relationship that may lead the child to eat poorly or be plagued
by constant anxiety. The nervousness can interfere with sleep or the
production of growth hormones. If failure to thrive has not persisted for
too long, it usually can be reversed in the short run through special
nutritional and medical intervention to help the child regain strength and
begin growing normally again.
There are many factors that can result in slow growth in children.
Between the ages of two and five, growth slows down and children take
on more adult bodily proportions. Usually growth is rather smooth during
the preschool period. Genetic and ethnic backgrounds affect its overall
rate, as do the quality of nutrition and children’s experiences with illness.
Children’s appetites are often smaller in the preschool years than in
infancy, and preschoolers become more selective about their food
preferences. If children fall behind in growth because of poor nutrition or
hormonal deficiencies, they often can achieve catch-up growth if slow
growth has not been too severe or prolonged. A few children suffer from
failure to thrive, a condition marked by reduced physical growth, possibly
as a result of family stress and conflict. Bibliography
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