2Plant cells vs. Animal cells Only plant cells have these:Both types of cell have these:5)Cell wallGives support to the cell1)NucleusThis controls the cell2)CytoplasmThis is the jelly like substance where chemical reaction take placeLarge vacuoleLarge space filled with cell sap6)3)Cell membraneControls what goes in and out of the cellChloroplastsWhere photosynthesis takes place7)4)MitochondriaEnergy is released here by respiration
3Complete this definition of Diffusion using the key words: Partially permeableDiffusionConcentrationGradientRandom movementParticlesDiffusion is the _______ __________ of ______ from where there are lots of particles ( high __________) to where there are less particles.We say the particles diffuse down a concentration _________.In cells, the cell membrane has small holes that allow small particles through, but not large molecules. We call this membrane ________ ________.The bigger the difference in concentration, the faster the rate of ________.
5OSMOSIS IS THE MOVEMENT OF WATER PARTICLES FROM WHERE THERE ARE LOTS OF THEM (Dilute solutions) TO WHERE THERE ARE NOT VERY MANY OF THEM (concentrated solutions) THROUGH A SEMI-PERMEABLE MEMBRANE (LIKE A CELL WALL)OSMOSIS
6Photosynthesis - The equation 1. What factors are needed to make glucose?2. What products are made by photosynthesis?
7Limiting factorsIf you alter the levels of light, carbon dioxide or change the temperature the rate of photosynthesis will change!
9Can you fill in this table? Mineral needsCan you fill in this table?MineralNeeded forDeficiency diseaseNitratesMagnesium
10Mineral needs Mineral Needed for Deficiency disease Nitrates Healthy leavesGood all round growthPurple leaves, poor growthMagnesiumTo make chlorophyllYellow leaves
11Food chains A food chain shows where the energy goes in a food chain (in other words, “what gets eaten by what”):RabbitCabbageFoxStoatThe arrows indicate where the energy is goingPlants convert the sun’s energy into food
12Pyramids of biomassIn this food chain we can see that the mass of organisms in each stage is less than in the previous stage:CabbageRabbitStoatFoxWe can draw a “Pyramid of Biomass” to show this pattern:Mass of foxesMass of stoatsMass of rabbitsMass of cabbages
13Energy flow in a food chain Consider the energy flow in this food chain:100%10%1%0.1%CabbageRabbitStoatFoxClearly, not all of the ___’s energy that becomes stored in the _______ will end up in the fox. Only around ______ is passed on to the next stage in each food chain.Energy is lost at each stage because of a number of reasons:Each organism has to ____, keep warm etcEnergy is lost through faeces (______)Words – 10%, move, sun, waste, cabbage
14Improving the efficiency of a food chain Clearly, food chains aren’t very efficient. How could the efficiency of a food chain be improved?1) Reduce the number of stages in the chain:FoxRabbitCabbageStoat2) Limit an animal’s movement or keep it warm:3) Use plant hormones to regulate the ripening of fruit
15Energy in food production Biomass and energy is lost at each stage of a food chain. The efficiency of food production can be improved by reducing the number of stages in our food chains. It would be most efficient if we all ate just plantsIf you stop animals moving around and keep them warm they lose a lot less energy which makes food production more efficient
16DecayDecay is carried out by micro-organisms which work faster in warm, moist conditions with a good supply of oxygen.The decay process releases substances that plants need to grow.
17Carbon cycleThe constant cycling of carbon is known as the carbon cycleCarbon dioxide is removed from the atmosphere by photosynthesisIt is returned to the atmosphere by respiration and combustionMicrobes that decay waste and dead matter respire and produce carbon dioxide
19EnzymesEnzymes are biological catalysts, they increase the rate of reactions.Enzymes are protein molecules made up of long chains of amino acids.When enzymes are denatured the active site changes shape.
20What happens at the active site? Boardworks GCSE Additional Science: BiologyEnzymesWhat happens at the active site?In the same way that a key fits into a lock, so a substrate is thought to fit into an enzyme’s active site. The enzyme is the lock, and the reactant is the key.++↔↔enzymereactant+enzyme-reactant complex↔products20
21Factors affecting enzymes Boardworks GCSE Additional Science: BiologyEnzymesFactors affecting enzymesIf the temperature and pH changes sufficiently beyond an enzyme’s optimum, the shape of the enzyme irreversibly changes.This affects the shape of the active site and means that the enzyme will no longer work.When this happens the enzyme is denatured.denaturednormalheatpH21
23Where are the enzymes found? AmylaseProteaseLipaseBileHydrochloric acidWhere are the enzymes found?
24Enzymes of digestion Teacher notes This activity could be used to check students’ understanding of chemical digestion.
25HomeostasisThe internal conditions of your body need to be controlled to maintain a constant internal environmentWaste products such as carbon dioxide and urea need to be constantly removedUrea is produced by your liver as you break down excess amino acids and is removed by your kidneys as urine
26Five factors we need to keep constant. 1. temperature2. water3. sugar4.waste products (need to remove)5. ionsB2 Homeostasis
27Use these words to complete the notes. receptors brain receptors The thermo-regulatory centre of the ______monitors and controls the temperature of blood as it passes through.This centre has __________which are sensitive to the temperature of the blood.The skin also has _________ sensitive to temperature.B2 Homeostasis
28Glucose controlYour blood glucose concentration is monitored and controlled by your pancreasInsulin and glucagon are the hormones involved in controlling blood sugar. Insulin converts glucose to glycogen and glucagon converts glycogen to glucoseIn diabetes the blood glucose may rise to fatally high levels because the pancreas does not produce enough insulin. It can be controlled by injections and diet
31Gregor Mendel (The Pea Plant Man) Why was his work not spread quickly?He was not a famous scientist – nobody knew about him at the time.His job as abbot stopped him giving lectures at universities.He published his work in an obscure journal that few people read.Biologists at the time did not think mathematics had anything to do with Biology.
32Disease Some disorders are inherited Huntington’s disease is caused by a dominant allele of a gene and can be inherited from only one parentCystic fibrosis is caused by a recessive allele of a gene and so must be inherited from both parents
33Cystic Fibrosis The treatment involves chest physiotherapy. They are very prone to chest infections and malnutrition.The mucus encourages the growth of pathogenic microbes that cause infection and cause long term lung damage.