life processes. 0.0 / 5 ? BiologyVariety of life and classificationGCSEEdexcel Created by: grainne martin-wellsCreated on: 14-10-13 12:53 what are the characteristics of living organisms? movement, reproduction, sensitivity, growth, respire, excretion, nutrition. 1 of 27 which organs excrete? lungs, kidneys, skin. 2 of 27 which organs are part of the circulatory system? heart, blood vessels (veins, capillaries, arteries) 3 of 27 what are the differences between plant and animal cells? plant cells have cell walls, chloroplasts and vacuoles animal cells don't. 4 of 27 what are the similarities betweens animal and plant cells? they both have cell membranes, cytoplasm, mitochondria and nucleuses. 5 of 27 what do the chloroplasts do? absorb light energy and perform photosynthesis? 6 of 27 what does the cell wall do? it is made of cellulose. it gives the cell structure. it supports the plant cells. it is not a barrier to water or dissolves substances. 7 of 27 what does the cell membrane do? it controls which substances pass in and out of the cells. 8 of 27 what does the vacuole do? it gives the cell structure. if it loses some of the cell sap within it the cell will become flaccid. 9 of 27 what is the role of mitochondria? chemical reactions happen within them. 10 of 27 why are chloroplasts green? because they contain a green pigment in them called chlorophyll. 11 of 27 what are enzymes? biological catalysts 12 of 27 why do we need enzymes? to speed up reactions within the cell because without them the reactions would happen too slowly to sustain life. 13 of 27 what will happen if the enzymes are exposed to temperatures of 35 degrees C? it is their optimum temperature so they will work at their fastest. 14 of 27 what will happen to enzymes if they are exposed to temps of above 40 degrees C? they will start to denature and work slower. 15 of 27 what will happen to enzymes if they are exposed to temps of over 50 degrees C? they will all be denatured and they will stop working. 16 of 27 what is the molecule that an enzyme acts on called? a substrate. 17 of 27 what is the area that the substrate attaches to called? the active site. 18 of 27 what does an enzyme do to speed up a reaction? it lowers the activation energy and allows the products to be formed more easily. 19 of 27 what are the 3 stages of enzyme action? the substrate enters the active sight, the reaction takes place and the products are formed and leave the active sight. 20 of 27 what is the optimum PH for an enzyme? it depends which enzyme it is, for instance an enzyme in the stomach works at an much lower PH than one in the mouth. 21 of 27 what is the word equation for aerobic respiration? glucose + oxygen = energy + carbon dioxide + water. 22 of 27 what is the word equation for anaerobic respiration? glucose = energy + lactic acid. 23 of 27 why do organisms respire? to get energy. 24 of 27 when would organisms anaerobically respire? when you sprint and you cant breathe in quick enough to get the oxygen to your muscles that they need. 25 of 27 what happens when yeast cells respire anaerobically? they produce ethanol and CO2 and eventually die if they produce too much ethanol. 26 of 27 what is the volume of oxygen needed to completely oxidise the lactic acid that builds up in the body during anaerobic respiration is called? oxygen debt 27 of 27
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