Question

DNA sequences can act as "tape measures of evolution” (see Concept 5.6). Scientists analyzing the human genome sequence were surprised to find that some of the regions of the human genome are mostly highly conserved (similar to comparable regions in other species) don't code for proteins. Propose a possible explanation for this observation.

Short answer

The conserved sequences are the sequences that do not code for the protein. These are the tape measures of the evolution present in the human genome that remain unchanged throughout generations.

Step-by-step solution

Description of DNA

DNA (deoxyribonucleic acid) is the genetic material present in every organism. It is encoded with the genetic information responsible for particular traits in an organism.

Conserved sequences 

The DNA sequence that does not change and is maintained by natural selection is known as the consensus sequence. The conserved sequences in the DNA component do not code for proteins that may be the regulator sequences present in the gene.

Step 3: Evolution and conserved sequences

The conserved sequences are evolutionarily and unaltered in a particular organism. For example, the ribosomal gene that does not code for a protein is the conserved sequence that remains unaltered in the span of evolution.

The conserved sequences are much crucial in the regulation of the coding genes producing proteins. Thus, mutation taking place in the conserved DNA sequences may result in a lethal effect on the organism.

The conserved sequences are transferred from one generation to another without any changes in their sequences. Thus, the conserved sequences act as the tape measures for evolution by maintaining hereditary.