bacteria
Pathogenesis is the process by which a microbe causes disease. Disinfection is the process of reducing the number of pathogens in a location.
yes it causes childlike symptoms
There are many causes of retardation. These includes Down syndrome, velocariofacial syndrome, fetal alcohol syndrome, problems during pregnancy and other genetic disorders.
Having an extra copy of chromosome 21. You are supposed to have 2; when you have 3 (trisomy 21), Down's Syndrome is the result.
See the Related Link to a very good FAQ on the causes of Down syndrome.
Down syndrome is purely genetic. There are no known environmental causes of the disorder. It is not a disease that is passed from parent to child. It is simply an disorder when the chromosomes split during cell division during development. The mayoclinic describes the causes: http://www.mayoclinic.com/health/down-syndrome/DS00182/DSECTION=causes
Down Syndrome is a the addition of an extra chromosome and not really related to evolution. It is more of a genetic mutation that causes this event to occur.
Quote from Wikipedia: "Irukandji syndrome is a condition induced by envenomization through the sting of Carukia barnesi, the Irukandji jellyfish, and other cubozoans.[1]"Note: Irukandji Syndrome has nothing to do with Down Syndrome and this question should NOT be placed in the Down Syndrome category!
dana hills high school
Well, honey, Down syndrome is caused by an extra copy of chromosome 21, also known as trisomy 21. It's like having a bonus chromosome that messes with the genetic party. So, to put it simply, trisomy 21 is the culprit behind Down syndrome.
Down's syndrome is caused by trisomy of the 21st chromosome. This is mostly caused when the chromosome pair fails to separate properly (nondisjunction).