Examen PAU Lengua Extranjera: Inglés 2022 Extraordinaria — Madrid

Text A Can our Bodies Withstand Global Heating? “Every human being is at risk from extreme heat – it’s a fact of life, your body needs to function in a certain environment,” says Mike McGeehin, environmental health epidemiologist. “And when that environment becomes extreme then you are at risk.” The impact of extreme heat on the human body is not unlike what happens when a car overheats. Failure starts in one or two systems, and eventually it takes over the whole engine until the car stops. The hypothalamus, located in the brain, regulates body temperature using information passed to it by temperature sensors in our skin, muscles, and other organs. When high temperatures are detected, the brain initiates a cascade of responses to help us cool down, such as sweating, increased respiration and the impulse to seek water and cooler environments. But when the system overheats, these responses start to fail, and miscommunication can occur in the brain, contributing to confusion, dizziness and altered behaviour. Each organ responds differently to extreme heat exposure, with symptoms that quickly become fatal or cause permanent damage from which the body may never fully recover. For instance, to sweat and cool off, blood flow shifts to the periphery of the body, causing a fall in blood pressure in vital organs. The heart starts to beat faster to compensate, but, if the person does not replenish their water reserves, blood pressure can drop dangerously and cause fainting. Between 1998 and 2017, more than 166,000 people died due to heat, according to the World Health Organization (WHO), and countries around the world are experiencing a year on year rise in record-breaking high temperatures. For many people, unendurable heat is becoming the new normal. It is most likely to disproportionately affect the poor, the sick – those with chronic conditions, or heart and kidney disease in particular – and older people. Adapted from “Too Hot to Handle: Can our Bodies Withstand Global Heating?” The Guardian, October 20, 2021. <https://www.theguardian.com/global-development/2021/oct/20/too-hot-to-handle-can-our-bodies-withstand-global-heating>