People often say they feel good when the sun is shining and sad when it is cloudy.In fact, sunlight makes us feel good.When sunlight hits our skins, our bodies produce a vitamin.Vitamins are natural chemicals(化学物质)which we all need to stay healthy.Sunlight helps our bodies produce vita...
题目The adrenal glands produce hormones. What are hormones? A. Chemicals that control body functions B. Food that we eat C. Air that we breathe D. Water that we drink 相关知识点: 试题来源: 解析 A。激素是“Chemicals that control body functions”(控制身体功能的化学物质)。选项 B、C、D ...
flowersaroundyourhome,sothatwhenitrains,chemicalsfromyourhomedonoteasilyflowinto thewater. 4 Theselawsaredirectedatindustries,hospitals,schoolsandmarketareasonhowto treatandmanagesewage(污水).Inmanydevelopedcities,wastetreatmentisveryefficient,and designedtoreducepollutionofwaterbodies. Therearealsolotsoforganizatio...
Deciding What Chemicals to Produce: Different PerspectivesGreenBiz Editors
orchemicalsusedinsyntheticfabrics(混合纤维), maycausesignificantairpollution. 4 Scientistscannotanswerthisquestionfor now,accordingtotheworldHealthOrganization.We doknowthatourbodiescannottakein“large”pieces ofmicroplastics.However,iftheplasticsaresmall enough,theycanfind waysintoourbodiesand staythereforalongtime...
Some of the worst offenders may be sulfur-containing chemicals; 其中最难闻的是含“硫”的化学物质, those give body odor its oniony aroma. 它使得体味有洋葱的气味。 Carboxylic acids are in the mix, too, adding notes of cheese. 羧酸也在其中,增加起司的味道。
Scientists have long known that nature is really a chemical factory. All living things contain chemicals that help them survive. So scientists" interest in traditional medicine is not new. But it has become an urgent concern. This is because the earth"s supply of natural medicines may be dropp...
Studies show that the output of crops rises when there’s a wider diversity of crops being grown on a farm, and money is saved since the need for harmful fertilizer and other chemicals is reduced. “The photographs of family farmers may tell just a few local stories, but the message is ...
What are the chemicals produced by the endocrine system? What is plant biochemistry? What biogeochemical cycle maintains the pH in soil? What four substances help preserve the remains of organisms? What is the process of transpiration in vascular plants?
(水力压裂) for oil and gas. In this process, water, sand, and chemicals are forced to flow underground under high pressure to fracture rocks to let natural resources out. As those resources, such as oil and natural gas, make their way to the surface, so do the water and chemicals that...