Crossing over... Occurs during prophase I
Is the exchange of genetic material between two homologous chromosomes
Produces genetic variations
All of the above

What is the following best defines climate?

Give examples of selective advantage of organism’s body part/organ

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?