Transcript Document
What are the advantages and disadvantages of the 2 methods of farming: Additive Reason C_________ To make food look attractive F_________ Improve taste S_________ Sweeten without adding sugar Organic E_________ To mix together ingredients that would normally separate intensive P_________ To prevent microbes growing A_________ To prevent fats and oils reacting with oxygen advantage disadvantage FARMING DIGESTION C3 – FOOD MATTERS FOOD SAFETY Why can nitrogen be lost from the soil as a result of intensive farming? How do farmers overcome the problem? E______ breakdown large molecules into smaller molecules that can be absorbed into the b______. Any excess a_____ a_____ are broken down in the l______ and excreted in u______. F_____ S______ A______ are a government agency which aim to make sure food is safe , healthy and fairly marketed. EVIDENCE NATURAL SELECTION HUMAN EVOLUTION What evidence is there that evolution is happening? D______ proposed the theory of e______ to explain how species change over time. There is v_______ between individuals, those that are better a_______ are more likely to s________ and r________, passing on favorable characteristics. How are human beings different from apes? • bigger b_____ • w_____ upright EVOLUTION SELECTIVE BREEDING What is selective breeding? B3 - Life on Earth LAMARCK Believed that acquired characteristic s can be inherited How does it differ from natural selection? COMMUNICATION SYSTEMS What resources are plants and animals in competition for? • • • Nerves EXTINCTION Causes of extinction: • increased c_______ • New p________ • e_________ change • new d_________ Speed of response Chemical or electrical How is it carried? Hormones Label the parts of the atom: Complete the table: P____ Type of radiation E_____ Stopped by.... Ionizing power (strong/poor /medium) α N_____ β Helium atom BACKGROUND RADIATION Where does background variation come from? ______________________ ______________________ ______________________ ______________________ Symbol Radioactive atoms are u_____ and decay emitting radiation. R______ d____ helps atoms to become more stable. As a radioactive atom decay its activity drops. H____ l_____ is the time it takes for radioactivity to halve, different substances have different h____ l_____. γ ATOMS TYPES OF RADIATION HALF-LIFE P3 – Radioactive Materials GENERATING ELECTRICITY Label the parts of a power station: RENEWABLE ENERGY NUCLEAR FISSION Come up with 3 renewable sources of energy which are alternatives to fossil fuels or nuclear power... Energy Source 1. 2. 3. 4. ______________ ______________ ______________ ______________ Advantage Disadvantage USES OF RADIOACTIVITY Give some examples of the uses of radioactivity: ________________ ________________ ________________ ________________ ________________ ________________ ________________ ________________ (Higher only) N_____ f_____ takes place in the nucleus of the a_____. A n______ is absorbed by a uranium nucleus. The nucleus is split releasing e______. A c_____ r______ can be started releasing further energy.