Consider the model depicting the dynamics within a specific population of birds. which input within this model is responsible for gene flow and therefore genetic variability within the existing bird population? a)birthsb)deathsc)emigrationd)immig ration

Compare asexual reproduction to sexual reproduction

Advances in technology have enabled scientists and researchers to better study the evolutionary relationships between species

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?