Is the rate of diffusion permanganate on Definition of diffusion Give examples of substances that gloves different for different agar and factors affecting diffuse into and out of cells. mask gases? Use concentrated investigate rate. forceps ammonium hydroxide and diffusion of Calculate and compare surface cotton wool hydrochloric acid in a large different acids Oxygen, carbon area: volume ratios. long glass dioxide and urea glass tube. and alkalis tube with passes through cell Explain how the small intestine Does temperature affect through agar strips of damp membranes by and lungs in mammals, and roots investigate rate of litmus along the rate of diffusion? Fresh diffusion. and leaves in plants, are adapted length beetroot placed in iced diffusion of for exchange of substances. beetroot water and warm water. glucose through Single celled beakers Record observations and cellulose tubing organisms have a Describe and explain how an kettle suggest explanations. use digital bigger surface area to exchange surface is made more ice microscope to volume ratio than effective. two gas jars of Watch a video or computer observe diffusion multicellular NO2 simulation of diffusion on BBC of particles in milk organisms, so transfer two empty gas or McGraw-Hill website. or yogurt solution. sufficient substances jars. diffusion. across their surface. Role play diffusion in gases Multicellular organisms Optional demo Observe slides or and liquids at different require specialised materials: micrographs of villi, temperatures and organ systems to beaker of alveoli, root hair cells concentrations. exchange sufficient water and leaves. Observe micrographs of substances. pot perm exchange surfaces in plants crystals and animals. Make drawings Calculate surface Factors affecting the straw and relate structure to function. area: volume ratios effectiveness of an forceps for different exchange surface. agar in test Produce a mind map to objects or using data tube or summarise diffusion and about organisms. exchange surfaces.
Definition of diffusion and factors affecting rate. Oxygen, carbon dioxide and urea passes through cell membranes by diffusion. Single celled organisms have a bigger surface area to volume ratio than multicellular organisms, so transfer sufficient substances across their surface. Multicellular organisms require specialised organ systems to exchange sufficient substances. Factors affecting the effectiveness of an exchange surface. Give examples of substances that diffuse into and out of cells. Calculate and compare surface area: volume ratios. Explain how the small intestine and lungs in mammals, and roots and leaves in plants, are adapted for exchange of substances. Describe and explain how an exchange surface is made more effective. Is the rate of diffusion different for different gases? Use concentrated ammonium hydroxide and hydrochloric acid in a large glass tube. Does temperature affect the rate of diffusion? Fresh beetroot placed in iced water and warm water. Record observations and suggest explanations. Watch a video or computer simulation of diffusion on BBC or McGraw-Hill website. Role play diffusion in gases and liquids at different temperatures and concentrations. Observe micrographs of exchange surfaces in plants and animals. Make drawings and relate structure to function. Produce a mind map to summarise diffusion and exchange surfaces. permanganate on agar investigate diffusion of different acids and alkalis through agar investigate rate of diffusion of glucose through cellulose tubing use digital microscope to observe diffusion of particles in milk or yogurt solution. diffusion. Observe slides or micrographs of villi, alveoli, root hair cells and leaves. Calculate surface area: volume ratios for different objects or using data about organisms. gloves mask forceps cotton wool long glass tube with strips of damp litmus along length beetroot beakers kettle ice two gas jars of NO2 two empty gas jars. Optional demo materials: beaker of water pot perm crystals straw forceps agar in test tube or
AQA-8464-SOW-CELLS.DOCX