Down Syndrome Essays -- essays research papers

Some clock times when meiosis ( the division of generative electric cells ) occurs, chromosomes may be lost, left behind, or too many may be passed on, resulting in the birth of a child with a transmissible or inherent smirch or disease. One of the virtually earthy of these genetic disorders is downwards syndrome. This disorder takes its name from Dr. Langdon Down, who was the first to describe it formally, in 1866.Down syndrome is a condition marked by abnormal natural and mental ontogeny that is caused by a genetic defect. This genetic defect is caused by an unnecessary chromosome. People born with Down syndrome have 47 chromosomes compared to the normal get along of 46, 23 chromosomes inherited from each parent. This extra chromosome originates more(prenominal) often in the mothers egg than the fathers sperm. Chromosomes are individual, large DNA molecules in a cell nucleus. They contain the genes along with structures that hold the DNA and aid it in expressing gene tic endowment by orchestrating cellular operations. Down syndrome is one of the most common chromosomal abnormalities, occurring in about 1 out of 800 births. However, the oftenness of the disorder varies greatly according to the age of the mother. For women in their twenties the respect is 1 in 2,000 but it rises steeply to 1 in blow by the time a woman reaches 40. Down syndrome is usually recognise soon aft(prenominal) birth because of characteristic facial features such as a shape nose, upward slanting of the eyes, a large expression that often protrudes from a smal... Down Syndrome Essays -- essays research papers Sometimes when meiosis ( the division of reproductive cells ) occurs, chromosomes may be lost, left behind, or too many may be passed on, resulting in the birth of a child with a genetic or congenital defect or disease. One of the most common of these genetic disorders is Down syndrome. This disorder takes its name from Dr. Langdon Down, who was the first to describe it formally, in 1866.Down syndrome is a condition marked by abnormal physical and mental development that is caused by a genetic defect. This genetic defect is caused by an extra chromosome. People born with Down syndrome have 47 chromosomes compared to the normal amount of 46, 23 chromosomes inherited from each parent. This extra chromosome originates more often in the mothers egg than the fathers sperm. Chromosomes are individual, large DNA molecules in a cell nucleus. They contain the genes along with structures that hold the DNA and aid it in expressing heredity by orchestrating cellular operations. Down syndrome is one of the most common chromosomal abnormalities, occurring in about 1 out of 800 births. However, the frequency of the disorder varies greatly according to the age of the mother. For women in their twenties the rate is 1 in 2,000 but it rises steeply to 1 in 100 by the time a woman reaches 40. Down syndrome is usually recognized soon after birt h because of characteristic facial features such as a flattened nose, upward slanting of the eyes, a large tongue that often protrudes from a smal...