| Is it true that cockroaches can survive a 
		nuclear bomb? In 1945 as the Second World War neared its end, 
		two atomic bombs were dropped on Hiroshima and Nagasaki in Japan. Much later, when the smoke had cleared, rumour has it that the only 
		survivor was a tiny insect known as a cockroach.
 As a result, tests were carried out on the insects to see if their 
		radiation defences were as tough as first thought.
 The two bombs that ended the war had a strength of around 10,000 radon 
		units. When exposed to this level during the experiment, the cockroaches 
		did survive. However, when the force was increased to 100,000, they all 
		died. Cockroaches are tough, but not invincible.
 The science explanation behind their amazing resilience is that they 
		have extremely simple and slow cell cycles which protects them from the 
		effect of the radiation. Cells are at their weakest to radiation when 
		they are dividing and, unlike humans, as this happens much less 
		frequently in cockroaches, they have a higher tolerance.
 Does this mean that cockroaches are invincible to a nuclear bomb then? 
		Well not exactly. They would probably disintegrate in the explosion and 
		fry in the heat of the blast. Also, don’t forget that the strength of 
		nuclear bombs these days is much greater than those of 1945.
 
		
		
		 Descarga GRATIS nuestra app de Podcast 
		para aprender Inglés (para Iphone, Ipad, Ipod y Android).
 
		 *Si 
		te ha resultado difícil el ejercicio o quieres practicar más dispones de más
 Ejercicios de Listening de nivel Intermedio.
 |  | 
 
 
 
		  |