The pesticide, DDT have been sprayed on acorn, oak leaf and leaf litter. Which living organism will have the highest concentration? Please give a reason.

Twind is considered to be an abiotic factor because it.?

What molecules will be best used to compare different species with the exact same sequence of amino acids? why would two species have the same protein even if the molecules in question is different? (hint: transcription to translation to protein).

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?