The Perfect Answer Revision Guide CIE Igcse Biology 2

The Perfect Answer Revision Guide CIE Igcse Biology 2 1. Characteristics and classification of living organisms................................................3 2. Organisation of the organism .....................................................................................7 3. Movement in and out of cells ...................................................................................10 4. Biological molecules.................................................................................................12 5. Enzymes ...................................................................................................................14 6. Plant nutrition ...........................................................................................................15 7. Human nutrition........................................................................................................16 8. Transport in plants....................................................................................................20 9. Transport in animals .................................................................................................22 10. Diseases and immunity ............................................................................................25 11. Gas exchange in humans .........................................................................................26 12. Respiration ...............................................................................................................28 13. Excretion in humans .................................................................................................29 14. Coordination and response ......................................................................................30 15. Drugs ........................................................................................................................34 16. Reproduction............................................................................................................35 17. Inheritance................................................................................................................40 18. Variation and selection .............................................................................................43 19. Organisms and their environment ............................................................................45 20. Biotechnology and genetic engineering...................................................................48 21. Human influences on ecosystems 50............................................................................ Copyright © Hazel Lindsey, Caroline Gillespie 2018 2 For use by WAQAR AHMED ONLY. Not for redistribution. Downloaded by john gatheca () lOMoARcPSD| Gathecha NOTE: Core content is given in this format (Grades 1-5). Supplementary content is given in italics (grades 5-9) 1. Characteristics and classification of living organisms Characteristics all living organisms show: • Movement • Respiration • Sensitivity • Nutrition • Excretion • Reproduction • Growth Define movement • Action by all or part of an organism • Causes change in position or place Define respiration • Chemical reactions in cells • Nutrient molecules broken down • Energy released for metabolism Define sensitivity • Detecting and responding to changes in the environment • Sensing stimuli in the internal or external environment • Making appropriate responses Define growth • Permanent increase in size • Increase in dry mass • Cell numbers and/or cell size increase Define reproduction • Processes that make more of the same kind of organism Define excretion • Removal from organisms of toxic materials and substances in excess of requirements • Removal of waste products of metabolism Define Metabolism • Chemical reactions in cells including respiration Define nutrition • Taking in materials for energy, growth and development Plants require: • Light • Carbon dioxide • Water • Ions Animals require: • Organic compounds • Ions • Usually need water Copyright © Hazel Lindsey, Caroline Gillespie 2018 3 For use by WAQAR AHMED ONLY. Not for redistribution. Downloaded by john gatheca () lOMoARcPSD| Gathecha What is a classification system? • System to classify organisms in to groups by the features they share What is a species? • Group of organisms that can reproduce to make fertile offspring The binomial system • Internationally agreed system to classify organisms • Two-part scientific names showing genus and species (e.g. Canis lupus) Traditional classification systems • Reflect evolutionary relationships • Based on morphology and anatomy What is a more accurate way to classify organisms? • Sequence of bases in their DNA • Sequences of amino acids in their proteins Explain how DNA sequence and ancestry are related • More recent ancestors share more similar base sequences in DNA Cells of all living organisms: • Cytoplasm • Cell membrane • DNA (as genetic material) • Ribosomes for protein synthesis • Enzymes involved in respiration List the 5 Kingdoms: • Animals • Plants • Fungi • Prokaryotes • Protoctists What feature makes a prokaryote? • No definite nucleus What feature makes a protoctist? • All the cells are the same Plants: • Have different types of cells • Have cell walls Fungi: • Have cell walls • Feed by external digestion Animals: • No cell wall • Different types of cells • Internal digestion What is a vertebrate? • An animal with a backbone