In what period did fish, mammals, reptiles, amphibians, and plants appear on earth?

An example of a trait that would be considered acquired and inherited is a. a cleft chin b. muscle tone c. scar tissue d. freckled skin

In the respiration-photosynthesis cycle shown above, what are the products of cellular respiration that belong in box 2?

Ivan is looking at a cross section of a stem taken from a vascular plant. he sees two different types of vascular tissue: the xylem, which is closer to the center of the stem, and the phloem, located around the xylem, closer to the outside of the stem. how do these two structures work together in a living plant?