Summarize how unicellular organisms may have
given rise to the first animals.

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

Ascientific idea becomes valid when it is what?

What factors contribute to the effect an environmental toxin has on the human body?