Answer:
Gas exchange during respiration occurs primarily through diffusion. Gas molecules move from a region of high concentration to a region of low concentration. Blood that is low in oxygen concentration and high in carbon dioxide concentration undergoes gas exchange with air in the lungs.
Explanation:
Answer:
i hate getting questions like these
Explanation:
Waves erode a beach by pressing continually against them, right? I have heard of this happening many times. What the people do is build a small trench around the outside of the beach so the waves filter down into it, then back out instead of washing up against the sand. The other thing they do is wait a couple years for the beach to go down, then they put in new sand during the winter.
<span>Please Rate me Brainliest, I need it alot. </span>
Answer: crossing over allows for genetic variation
Explanation:
crossing over is the exchange of genes between two chromosomes which ends up resulting in non-identical chromatids that comprise the genetic material of gametes (sperm and eggs).
Basically crossing over makes the chromatids that are held together by a centromere, no longer identical to eachother which creates genetic variation.