What is the difference between an "old" and a "new" strand of dna?

Match the examples to the correct level of organization. 1. system level roses, snakes, puppies 2. organism level roots, stamens, leaves 3. tissue level bone, cartilage, blood 4. organ level heart, veins, arteries

How can an organ, such as the lungs, work for multiple body systems?

Which is the best example of plant tissue? the answer is d (just took the test)