[Solved] With both bacterial and eukaryotic cells constantly dying and breaking down around us, and with a tremendous load of fragmentary DNA washing around in the fluid world, why aren't genes being transferred among various living organisms at a massive scale daily? A) DNA that is not protected inside a protein coat or membrane is very vulnerable. B) Living cells maintain a very effective barrier to the introduction of large molecules. C) Since a vector appears necessary to snatch up DNA from one protected source and inject it into a cell, "naked" DNA is apparently vulnerable and unable to cross membranes easily. D) All of the choices are correct. E) None of the choices are correct, since DNA is readily exchanged among all organisms in nature. Tolerance: The process by which the body becomes less responsive to a substance or a stimulus after repeated exposure. Nicotine: A stimulant and addictive substance found in tobacco, impacting the nervous system by increasing alertness and reducing stress. Mental Alertness: The state of being watchful and ready to respond quickly to any potential danger or challenges. Anxiety: A mental health disorder characterized by feelings of worry, anxiety, or fear that are strong enough to interfere with one's daily activities.