Petra finds a discolored stain on the carpet at a suspected crime scene. What two presumptive tests might she use to determine if the stain is blood? First, Petra sprays the discolored area with , which returns a glowing blue color. However, she knows that this chemical might also turn blue with other substances that contain iron. Subsequently, she uses , which turns pink, indicating the presence of hemoglobin.

How is ribosomal rna useful as a molecular clock? a. a large portion of the dna ring is not vital to structure or function, allowing it to accumulate neutral mutations. b. its rate of mutation increases over time as organisms continue to evolve and differentiate from each other. c. a slow mutation rate makes it useful for determining evolutionary relationships between ancient species. d. it is only found in select organisms, making it easier to compare relationships between species that have it.

Amajor source of energy for your body comes from

As soon as i live in alabama and i have question to me with a report. or rather a statement. the statement i need with: discuss the influence of cost and availability on your states (alabama) statistics. i really need to complete this. so anything will ! 20 points are up for grabs to the most !