The Physical Development Of A Human Being Essays - Fertility

The Physical Development Of A Human Being Catherine The Physical Development of a Human Being As defined in Berk's, Development Through the Lifespan, physical development is changes in body size, proportions, appearance, and the functioning of various body systems; brain development; perceptual and motor capacities; and physical health. The physical development of a human being is the unique because of all of the visible changes that every human being goes through. Physical growth results from a continuous and complex interplay between heredity and environment. Humans begin to develop before they are out of their mother's womb. After conception, the zygote is what I consider the earliest development of the human being. The period of the zygote is about two weeks long. The zygote then becomes an embryo. The period of the embryo lasts from the second week on through the eighth week of pregnancy. The embryo then changes to form the fetus. The period of the fetus is from the ninth week until the end of the pregnancy. The zygote, embryo, and fetus all form in the first trimester o r pregnancy. By the third trimester, the fetus is around seven and half pounds. I weighed about eight and one fourth pounds when I was born. My mother still tells me that when I was born I had enough hair to braid. She says all my hair gave her horrible heartburn. Luckily she did not smoke or use any drugs or alcohol during the time that she was pregnant with me. All of these things can do serious harm to the fetus. Boys tend to be a little longer and heavier than girls at birth. Babies change faster than older humans do. The human body grows and enlarges at the most rapid rate during the first two years. Weight is gained steadily during this time. By nine months baby fat has usually arrived and is at its highest level. This helps babies to maintain a constant body temperature. Babies become thinner during the second year. This held true for me from what I have seen of my baby pictures. Babies do not tend to be very muscular or coordinated. The child grows and size increases, and different parts of the body grow at different speeds. There are two growth patterns that represent this. The first is called the cephalocaudal trend. During this phase the head takes up a fourth of the body and the legs take up a third. The second pattern is called the proximodistal trend. This is when the growth proceeds from the center of the body outward. During infancy, the arms and legs continue to grow ahead of the hands and feet. The brain is closer to adult size at birth than any other body part on a baby. When a child reaches the age of two, the brain is already at seventy percent of its adult weight. Some of the factors that influence this early growth are heredity, nutrition, and emotional well-being. Over the first year of life, babies begin to organize sounds into complex patterns. During the second half of the first year, babies begin focusing on larger speech units. These larger units are critical to figuring out the meaning of what babies hear. By nine months babies begin to listen to speech for much longer periods of time, and they begin to perceive it on wordlike segments. A child's vision goes through some extensive changes during the first seven to eight months of the child's life. The child's vision improves a great deal throughout the first year. When a child begins some form of independent movement, they begin to better understand depth perception. When an adult moves around on his/her own, they too have a better feel for landmarks and what is around them. The rapid growth in body size that takes place in infancy begins to slow down in early childhood. During this time boys still tend to be a little larger than girls are. When I was this age, all of my friends were boys, and they were a little larger than I was. Increasing control of the child's hands and fingers lead to a huge improvement in the fine motor skills. Their drawings become more and more