How many different types of bases can be found on dna?

How do you know that the plant cells in these two images have different jobs, or functions? a. because all plant cells serve different functions b. because they are two different colors c. because their dna are different d. because their structures are different

The same agricultural practices are used in every country of the world. select the best answer from the choices provided t f

Vessels draining the myocardium of the heart, open primarily ,into which chamber?