Which pathway correctly represents protein synthesis?
proteins to rna to dna
rna to dna to proteins
dna to rna to proteins
dna to proteins to rna

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.

The cactus has adapted a great deal to survive hard conditions. Two examples of these are:

-Thick skin that keeps moisture inside and reflects heat.
-Spikes that keep animals and insects from drinking the water stores inside or eating the plant.