Biology Lab Scientific Paper Down syndrome is a condition in which a person has an extra chromosome. Chromosomes are small “packages” of genes in the body. They determine how a baby’s body forms during pregnancy and how the baby’s body functions as it grows in the womb and after birth. Usually, a baby is born with 46 chromosomes but babies with Down syndrome have an extra copy of one of these chromosomes, chromosome 21 . A medical term for having an extra copy of a chromosome is thirsty. Down syndrome is also referred to as Thirsty 21 .This extra copy changes how the baby’s odd and brain develop, which can cause both mental and physical challenges for the baby. Some features of Down syndrome would include having small ears, a flattened face, almond shape eyes, small hands and feet, small pinky fingers, poor muscle tone or loose Joints, and they tend to be shorter in height as children and adults.
There are three different types of Down syndrome. They are all very similar because the physical features and behaviors are alike. The three different types of Down syndrome include Thirsty 21 , Translation Down syndrome, and Mosaic Down syndrome.Thirsty 21 is when each cell in the body has 3 separate copies or chromosome 21 instead of the usual 2.
Thirsty 21 is what about 95% of people with Down syndrome have. Translation Down syndrome is the type that occurs when an extra part or an extra chromosome 21 is present, but it attached to a different chromosome rather than being a separate chromosome 21 . Mosaic Down syndrome is a type that affects about 2% of people with Down syndrome. For children with mosaic Down syndrome some of their cells have three copies of chromosome 21, but other cells have the typical two copies of chromosome 21 .Children with mosaic down syndrome have fewer features of the condition due to the presence of some cells with a typical number of chromosomes. Some research was done at Stanford University and based on the evidence from people with Down syndrome and studies in mouse models, they hypothesized that cognitive dysfunction is in part due to abnormalities in the structure and function of synapses.
Because there are more chromosome 21 genes in people with Down syndrome, there is increased gene activity. Standard’s hypothesis is that the activity of one or more of these extra genes leads to cognitive impairments.More than 85 perfect of children are born to mothers younger than 35 years old. It has been known for some time that the risk of having a child with Down syndrome increases with advancing age of the mother and occasionally the father. The older the mother, the greater the possibility that she may have a child with Down syndrome. Although many theories have been developed, it is not known what actually causes Down syndrome. Some professionals believe that hormonal abnormalities, X-rays, viral infections, immunologic problem, or genetic predisposition may be the cause of the improper cell division resulting in Down syndrome.