Bed bugs might sound like an old-fashioned problem, but now they are back with a vengeance. Fifty years ago, the blood-sucking pests were nearly eradicated in the United States thanks in part to the use of pesticides like DDT. Today, they are creeping over sheets and tormenting sleepers across the country. New York was recently declared America's most bed-bug-infested city in America. In the past, we countered the bed bugs by using pesticides called pyrethrins and pyrethroids. These compounds work by attacking the nervous system. Insects have channels in the membranes of their nerve cells that can be opened to allow sodium into the cells, triggering a nerve impulse. Pyrethrins and pyrethroids alter the nervous system by binding to the sodium channels, locking them in the open position. This allows sodium to pour into the cell continuously, causing the nerve to fire repeatedly and eventually leading to paralysis. Todays bed bugs seem to be more resistant to the chemicals that previously killed them. Cases of resistance have been reported in all classes of pests: crop diseases, human diseases, weeds, rodents, and insects, with crises in insect control beginning shortly after the introduction of pesticide use in the 20th century. Why do insect pests become resistant so readily to the pesticides used for control

Cells destroy body cells infected by a virus or bacteria. killer t t memory t none of the above

If jane has the blood type ab and marries john who has type o blood what are the possible phenotypes of their first kid?

Me plz he did not infringe upon the policy making powers that he felt the constitution gave congress. but the determination of foreign policy became preponderantly a presidential concern. when the french revolution led to a major war between france and england, washington refused to accept entirely the recommendations of either his secretary of state thomas jefferson, who was pro-french, or his secretary of the treasury alexander hamilton, who was pro-british. rather, he insisted upon a neutral course until the united states could grow stronger. which provides the best objective summary of this excerpt? president washington made a good choice when he decided not to accept the recommendations of his advisors and instead insisted that the united states stay neutral during the war between france and england as president, washington believed that the united states should remain neutral in foreign policy even though he had advisors who recommended that he take sides during the war between france and england. washington did not make policy decisions during his presidency because he did not want to interfere with the policy-making powers that the constitution gave congress. washington refused to accept entirely the recommendations of either his secretary of state thomas jefferson, who was pro-french, or his secretary of the treasury alexander hamilton, who was pro-britis