The correct sequence is DNA to RNA to Protein. This is in fact a summary of the central dogma of molecular genetics.
DNA, found in the nucleus of the (eukaryotic) cell, is the store of all hereditary information in the cell and this is basically information on all types of proteins of the body. In the nucleus, information for a particular protein is copied (transcribed ) from DNA and onto messenger RNA (mRNA).
mRNA then leaves the nucleus enters the cell cytoplasm where it attaches to a ribosome. Transfer RNA (tRNA) reads (translates) the information on the attached mRNA and brings up amino acids corresponding to the information. The amino acids are linked together in the ribosome into a chain which forms the primary structure of proteins.
Trisomy 21 (nondisjunction) Down syndrome is usually caused by an error in cell division called "nondisjunction." Nondisjunction results in an embryo with three copies of chromosome 21 instead of the usual two. Prior to or at conception, a pair of 21st chromosomes in either the sperm or the egg fails to separate.
Crust- topmost layer, made out of solid silicate rocks like basalt and granite, 200 C to 400 C
Mantle- composed of rocky oxides and silicates 500 C to 900 C
Core- mostly iron, or other metals 6,000 C