Choose all answers that could reasonably complete this sentence. DNA in the nucleus of cells in the liver and DNA in the epithelium lining of the digestive tract.
1. consists of genes that code for proteins; there is no DNA in the nucleus that has a regulatory function
2. is identical, if the liver and digestive tract are in the same individual
3. is identical in nucleotide sequence, but different cell types have different mutations
4. is different; each cell type only has one or two chromosomes with genes that code for the functions of that cell type.
5. has regions of homology (similarity), but is not identical, even if the liver and digestive tract are in the same person.