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1、【精品文档】如有侵权，请联系网站删除，仅供学习与交流IGCSE Biology(生物).精品文档.IGCSE Biology 2012http:/www.s-cool.co.uk/gcse/biologyhttp:/ of living things1 List and describe the characteristics of living organisms.Assimilation is a much better word than nutrition (because plants taking in and using CO2 and H2O is not nutrition
2、but is assimilation). The word assimilation in biology means taking in substances from the surrounding environment and building them into your own structures.Sensitivity leads to a response.Respiration is one of the biochemical reactions of cell metabolism.So we can produce an alternate list.GrowthA
3、ssimilation (replaces nutrition)Metabolism (includes respiration)ExcretionResponse (sensitivity)ReproductionGAMER2AssimilationTaking in inorganic and organic chemicals from the surrounding environment, and using them for cell construction and cell metabolism.MetabolismAll the chemical reactions that
4、 occur in a cell and result in what we call life.ExcretionRemoval of the waste products of metabolism from a cell.SensitivityUsing the sense organs to notice change.ResponseReacting to external change from the environment.ReproductionProducing new cells from pre-existing cells.To be a living thing s
5、omething must exhibit all of GAMER2 and be made of cells.Cell structure and organisation1 State that living organisms are made of cells. Everything, from bacteria to plants to insects to animals are all made of one (unicellular) or more cells (multicellular)Cell TheoryLiving organisms are composed o
6、f cells.Cells are the smallest unit of life.Cells come from pre-existing cells.2 Identify and describe the structure of a plant cell (palisade cell) and an animal cell (liver cell), as seen under a light microscope. 3 Relate the structures seen under the light microscope in the plant cell and in the
7、 animal cell to their functions.(a) cell surface membrane, which controls what enters and leaves the cellThe cell membrane allows diffusion of simple substances without control (passive transport), e.g. movement of oxygen into the cell, carbon dioxide out of the cells and ions into or out of the cel
8、ls. Additionally the membrane proteins can control movement of substances into or out of the cell and against a concentration gradient (if needed). The cell uses ATP energy to do this (active transport)(b) nucleus, which contains DNA which is inherited, and which controls the activities of the cell
9、Nuclear DNA contained within the cell carries the messages of life (genes).Genes tell the cell how to build specific proteins needed for all the functions of a cell.(c) chloroplasts, in which photosynthesis takes placeChloroplasts are membrane bound organelles found in green plants. Each chloroplast
10、 contains a green pigment protein molecule called chlorophyll, which is capable of using the energy from sunlight to produce glucose during photosynthesis.(d) cell wall, provides support to the cell so it can maintain its shape. It also help to prevent damage to the cell membrane.The cell wall has l
11、arge spaces in it allowing anything to pass easily, it is fully permeable.4 Describe the differences in structure between typical animal and plant cells. Animal CellsPlant cellsNo cell wallCell wallNo vacuoleMay have a vacuole, but not alwaysNo chloroplastsChloroplasts in photosynthesizing cellsHete
12、rotrophic must take in organic molecules from the surrounding environmentAutotrophic can make their ownOrganic molecules from inorganicMolecules using photosynthesis.Use the organic molecules- Glucose- Lipids- Amino acids- Nucleic acidsUse the inorganic molecules- Water- Carbon dioxide- Nitrates- Ph
13、osphatesRely on plants for foodSelf sufficient5 Calculate magnification and size of biological specimens using millimetres as units.Magnification = Drawing or image size for the specimen biological(mm)Actual size of the biological specimen (mm) How big is a cell?http:/ in and out of cells1 Define di
14、ffusion as the net movement of molecules from a region of their higher concentration to a region of their lower concentration down a concentration gradient, as a result of their random movement.Diffusion, Brownian motionhttp:/highered.mcgraw- CO2, and small ions can diffuse in or out of cells.2 Describe the importance of diffusion of gases and solutes and of water as a solvent.ing organisms Water (H2O) is not an organic compound but it is essential for life on Earth. Cell membranes are shaped into hollow spheres because of the polar nature of wa
