📚 KS3 Edexcel Biology Key Terms Memory Guide | KS3 Edexcel 生物词汇术语速记指南
Mastering biology at Key Stage 3 means more than just understanding processes – it means building a solid vocabulary. This guide gathers the most important Edexcel KS3 biology terms, explains them clearly, and gives you memorable tricks to make them stick. Whether you are learning about cells, ecosystems or genetics, having the right words at your fingertips will boost your confidence and your grades.
掌握 KS3 阶段的生物，不仅是理解过程，更是建立扎实的词汇基础。这份指南汇集了 Edexcel KS3 生物最重要的术语，清晰地解释它们，并为你提供难忘的记忆技巧。无论你正在学习细胞、生态系统还是遗传学，随时拥有正确的词汇都将提升你的自信和成绩。
1. The Building Blocks – Cells and Microscopy | 构建模块——细胞与显微技术
The cell is the smallest unit of life. All living things are made of cells, and using a microscope lets us see structures that are invisible to the naked eye. Key words here include cell membrane (the outer boundary that controls what enters and leaves), cytoplasm (jelly-like substance where chemical reactions happen), nucleus (contains genetic material and controls the cell), mitochondria (tiny powerhouses where respiration releases energy) and cell wall (a rigid outer layer found only in plant cells, made of cellulose). In plant cells you will also meet chloroplasts (green discs that absorb light for photosynthesis) and a large vacuole (keeps the cell firm).
细胞是生命的最小单位。所有生物都由细胞构成，使用显微镜可以让我们看到肉眼看不见的结构。这里的关键词包括细胞膜（控制物质进出的外层边界）、细胞质（发生化学反应的果冻状物质）、细胞核（含有遗传物质并控制细胞）、线粒体（通过呼吸作用释放能量的小型动力工厂）以及细胞壁（仅存在于植物细胞中，由纤维素构成的坚硬外层）。在植物细胞中你还会遇到叶绿体（吸收阳光进行光合作用的绿色圆盘）和一个巨大的液泡（维持细胞硬挺）。
To remember the difference between animal and plant cells, use the mnemonic ‘Cows Can’t Vanish’ – Cell wall, Chloroplasts, Vacuole are the three extra features in plant cells. When using a light microscope, you need to know the magnification = eyepiece lens × objective lens. Think of ‘Mighty Eye’ – Multiply Eyepiece by Objective.
为了记住动植物细胞的区别，可以使用助记符「Cows Can’t Vanish」——Cell wall（细胞壁）、Chloroplasts（叶绿体）、Vacuole（液泡）是植物细胞多出的三个特征。使用光学显微镜时，你需要知道放大倍数 = 目镜倍数 × 物镜倍数。把它想象成「Mighty Eye」（强大的眼睛）——Multiply Eyepiece by Objective（目镜与物镜相乘）。
2. Seven Life Processes – MRS GREN | 七大生命过程——MRS GREN
All living organisms carry out seven life processes, often remembered by the acronym MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion and Nutrition. Movement can be as obvious as running or as subtle as a plant turning towards sunlight. Respiration is the release of energy from food – do not confuse it with breathing! Sensitivity is detecting and responding to changes in the surroundings. Growth means increasing in size or cell number. Reproduction is producing offspring. Excretion is getting rid of waste products made by the body’s chemical reactions. Nutrition means taking in and using food.
所有生物都进行七大生命过程，常由首字母缩写词MRS GREN来记忆：Movement（运动）、Respiration（呼吸作用）、Sensitivity（感应）、Growth（生长）、Reproduction（生殖）、Excretion（排泄）和Nutrition（营养）。运动可以像奔跑一样明显，也可以像植物向光弯曲那般微妙。呼吸作用是从食物中释放能量——不要把它和呼吸（breathing）搞混！感应是探测并回应周围环境的变化。生长意味着体积或细胞数量的增加。生殖是产生后代。排泄是清除身体化学反应产生的废物。营养指摄取和利用食物。
A quick tip: when you see an unfamiliar organism in an exam question, run through the MRS GREN checklist. If it performs all seven, it is alive. Remember ‘My Rabbit Sings Good Rock Every Night’ or create your own wacky sentence.
一个快捷技巧：在考题中遇到一种不熟悉的生物时，过一遍 MRS GREN 核对清单。如果它能完成全部七项，它就是活的。记住「My Rabbit Sings Good Rock Every Night」（我的兔子每晚唱摇滚）或者自己编造一句荒诞的句子。
3. Human Organ Systems – A Team of Tissues | 人体器官系统——组织的团队合作
Cells work together to form tissues, tissues build organs, and organs make up organ systems. The human body relies on several key systems. The digestive system breaks down large insoluble molecules into small soluble ones that can be absorbed into the blood. Key organs: mouth, oesophagus, stomach, small intestine, large intestine. The circulatory system transports oxygen, nutrients and waste, using the heart as a pump and blood vessels as pipes. The respiratory system brings oxygen into the body and removes carbon dioxide; gas exchange happens in the alveoli. The skeletal system provides support and protection, while muscles work with bones to create movement. The nervous system carries electrical signals along neurones.
细胞共同构成组织，组织构成器官，器官构成器官系统。人体依赖几个关键系统。消化系统将大分子的不溶性物质分解成可以被血液吸收的小分子可溶性物质。关键器官：口腔、食道、胃、小肠、大肠。循环系统以心脏为泵、血管为管道运输氧气、营养物质和废物。呼吸系统将氧气带入体内并排出二氧化碳；气体交换在肺泡中进行。骨骼系统提供支撑和保护，而肌肉与骨骼一起产生运动。神经系统沿神经元传递电信号。
Link the hierarchy with the phrase ‘Cats Talk On Sofas’ – Cells → Tissues → Organs → Systems. To remember the order of the digestive tract, try ‘Mum Only Saw Little Insects’ – Mouth, Oesophagus, Stomach, Large intestine (but careful: small then large, so maybe ‘Mum Only Saw Snakes Laughing’ works too).
用短语「Cats Talk On Sofas」来串联层级——Cells（细胞）→ Tissues（组织）→ Organs（器官）→ Systems（系统）。要记住消化道的顺序，可以试试「Mum Only Saw Little Insects」——Mouth（口腔）、Oesophagus（食道）、Stomach（胃）、Large intestine（大肠）（但要小心：先小肠后大肠，所以也可以编成「Mum Only Saw Snakes Laughing」）。
4. Plant Nutrition – Photosynthesis Unlocked | 植物营养——解锁光合作用
Plants make their own food using a process called photosynthesis . The word itself gives away the meaning: photo = light, synthesis = putting together. In the chloroplasts, carbon dioxide and water combine using light energy to produce glucose and oxygen. The balanced word equation is:
carbon dioxide + water → glucose + oxygen
Plants use glucose for respiration, to make cellulose for cell walls, and to store energy as starch. The mineral nitrate from soil is needed to make proteins. Deficiency causes stunted growth and yellow leaves.
植物通过光合作用制造自己的食物。这个词本身就揭示了含义：photo = 光，synthesis = 合成。在叶绿体中，二氧化碳和水利用光能结合，产生葡萄糖和氧气。平衡后的文字方程式为：
二氧化碳 + 水 → 葡萄糖 + 氧气
植物利用葡萄糖进行呼吸作用，制造细胞壁所需的纤维素，以及将能量储存为淀粉。土壤中的矿物硝酸盐是制造蛋白质所必需的。缺乏会导致生长迟缓、叶片发黄。
Chant ‘CO₂ and H₂O make glucose, O₂ let go!’ to remember the inputs and outputs. A test for starch uses iodine solution: it turns blue-black if starch is present. Just think ‘Iodine finds the starch, turns it dark’.
吟唱「CO₂ 和 H₂O 生成葡萄糖，O₂ 跑掉！」来记住输入和输出。检测淀粉时使用碘液：如果有淀粉，它会变成蓝黑色。只要记着「碘找到淀粉，把它变深色」。
5. Respiration – Energy for Life | 呼吸作用——生命的能量
Respiration is not just breathing in and out; it is the chemical reaction that releases energy from glucose in every living cell. Aerobic respiration uses oxygen and produces a lot of energy:
glucose + oxygen → carbon dioxide + water (+ energy)
When your muscles work hard and cannot get enough oxygen, they switch to anaerobic respiration, which releases less energy and produces lactic acid. Lactic acid build-up causes muscle fatigue and cramps. In yeast, anaerobic respiration produces ethanol and carbon dioxide – a process called fermentation, used in baking and brewing.
呼吸作用不仅仅是吸气和呼气；它是每个活细胞从葡萄糖中释放能量的化学反应。有氧呼吸使用氧气，并释放大量能量：
葡萄糖 + 氧气 → 二氧化碳 + 水（+ 能量）
当你的肌肉高强度运动且无法获得足够氧气时，就会转为无氧呼吸，释放较少的能量并产生乳酸。乳酸堆积会导致肌肉疲劳和抽筋。在酵母中，无氧呼吸产生乙醇和二氧化碳——这个过程称为发酵，被用于烘焙和酿造。
Compare the two: Aerobic = Air Only, a lot of energy; Anaerobic = No Air, a little energy. Remember lactic acid with the phrase ‘Lactic makes you Lazy’.
比较这两种呼吸：Aerobic = Air Only（只用空气），能量多；Anaerobic = No Air（不用空气），能量少。用短语「Lactic makes you Lazy」（乳酸让你懒洋洋）记住乳酸。
6. Reproduction – Passing on Life | 生殖——生命的延续
Reproduction can be sexual (involving two parents, producing genetically varied offspring) or asexual (one parent, offspring are clones). In humans, the male gamete is the sperm and the female gamete is the egg (ovum). Fertilisation happens when the sperm nucleus fuses with the egg nucleus to form a zygote. The zygote divides to become an embryo. The placenta allows nutrients and oxygen to pass from mother to baby while preventing mixing of blood. In flowering plants, pollination transfers pollen from the anther to the stigma, leading to fertilisation inside the ovule, which becomes a seed.
生殖可以是有性（涉及两个亲本，产生遗传上多样的后代）或无性（一个亲本，后代为克隆体）。在人类中，雄配子是精子，雌配子是卵子。受精发生精子的细胞核与卵子细胞核融合形成受精卵时。受精卵分裂形成胚胎。胎盘允许营养物质和氧气从母体传递给婴儿，同时阻止血液混合。在开花植物中，授粉将花粉从花药转移到柱头，导致胚珠内受精，胚珠发育成种子。
Link the key terms with ‘Speedy Egg Zips Into Embryo’ – Sperm, Egg, Zygote, Embryo. For plant reproduction: ‘Ants Play Soccer’ – Anther, Pollen, Stigma. Seed dispersal methods are wind, water, animal and explosion – think ‘WWW.AE’ (Wind, Water, Animal, Explosion).
用「Speedy Egg Zips Into Embryo」串联关键术语——Sperm（精子）、Egg（卵子）、Zygote（受精卵）、Embryo（胚胎）。对于植物生殖：「Ants Play Soccer」——Anther（花药）、Pollen（花粉）、Stigma（柱头）。种子传播方式有风、水、动物和弹射——想想「WWW.AE」（Wind、Water、Animal、Explosion）。
7. Genetics and Inheritance – The Code of Life | 遗传学与遗传——生命的密码
Inside the nucleus, genetic information is stored in DNA, which is organised into structures called chromosomes. A short section of DNA that codes for a characteristic is a gene. Different forms of the same gene are called alleles. An individual with two identical alleles for a trait is homozygous; with two different alleles, heterozygous. The physical appearance is the phenotype, while the genetic makeup is the genotype. A dominant allele (capital letter) will mask a recessive allele (lower case).
在细胞核内，遗传信息储存在DNA中，DNA 被组织成称为染色体的结构。编码某一特征的一小段 DNA 叫做基因。同一基因的不同形式称为等位基因。拥有两个相同等位基因的个体是纯合子；拥有两个不同的等位基因，则是杂合子。外表看到的特征是表现型，而基因组成是基因型。显性等位基因（大写字母）会掩盖隐性等位基因（小写字母）。
Use a Punnett square to predict offspring combinations. Imagine the sentence ‘Domineering Genes Hide Shy Ones’ to recall dominant masking recessive. The phrase ‘Homo same, Hetero different’ helps split homozygous and heterozygous. Remember ‘Phenotype = Physical, Genotype = Genetic’.
使用旁氏方格预测后代的组合。想象句子「专横的基因隐藏害羞的基因」来记显性掩盖隐性。短语「Homo same, Hetero different」有助于区分纯合子和杂合子。记住「表现型看外表，基因型看基因」。
8. Ecology – Organisms in Their Environment | 生态学——环境中的生物
Ecology studies how living things interact with each other and their surroundings. A habitat is where an organism lives. A population is all the organisms of one species in a habitat. Different populations form a community. The community plus the non-living (abiotic) factors make up an ecosystem. Biotic factors include predators, food availability and disease; abiotic factors include temperature, light intensity, water and soil pH. A food chain shows the flow of energy, always starting with a producer (usually a green plant), followed by primary consumer, secondary consumer and so on. Interconnected food chains form a food web.
生态学研究生物彼此之间以及与其环境的相互作用。栖息地是生物居住的地方。种群是同一栖息地内同一物种的所有个体。不同的种群组成群落。群落加上非生物（无生命）因子构成一个生态系统。生物因素包括捕食者、食物来源和疾病；非生物因素包括温度、光照强度、水和土壤 pH 值。食物链显示能量流动，总是以生产者（通常是绿色植物）开始，随后是初级消费者、次级消费者等。相互连接的食物链形成食物网。
Order the levels: ‘Individual People Can’t Eat’ – → Ecosystem. For the food chain direction, remember the arrow points to the eater, meaning ‘is eaten by’. The sun is the ultimate source of energy for almost all food chains.
排序层级：「Individual People Can’t Eat」——个体 → 种群 → 群落 → 生态系统。对于食物链的方向，记住箭头指向捕食者，表示「被……吃」。太阳是几乎所有食物链的终极能量来源。
9. Microbes and Disease – The Invisible World | 微生物与疾病——看不见的世界
Microorganisms, or microbes, are tiny living things that can only be seen with a microscope. The main groups are bacteria, viruses and fungi. Bacteria are single-celled organisms that lack a nucleus (prokaryotes). They reproduce quickly by binary fission. Some bacteria are harmful, causing diseases like food poisoning, while others are useful (yoghurt making, decomposition). Viruses are even smaller and can only reproduce inside a living host cell. Fungi include yeasts and moulds; they feed by extracellular digestion. Many diseases are spread by pathogens. The body defends itself with barriers like skin, and with white blood cells that engulf invaders and produce antibodies.
微生物即微小的生物，只能通过显微镜看到。主要类群包括细菌、病毒和真菌。细菌是缺乏细胞核的单细胞生物（原核生物）。它们通过二分裂快速繁殖。有些细菌有害，会引起如食物中毒等疾病，而其他细菌则有用（制作酸奶、分解作用）。病毒更小，只能在活的宿主细胞内繁殖。真菌包括酵母和霉菌；它们通过细胞外消化取食。许多疾病由病原体传播。身体通过皮肤等屏障防御，并通过吞噬入侵者并产生抗体的白细胞进行防御。
Distinguish bacteria and viruses: ‘Bacteria Eat Food; Viruses Invade Cells’. The terms epidemic (wide spread in a country) and pandemic (global spread) can be linked to P for Planet. Remember ‘Antibodies are like body’s soldiers’.
区分细菌和病毒：「细菌吃食物；病毒入侵细胞」。术语epidemic（流行病、一国范围内广泛传播）和pandemic（全球大流行）可以与 P 代表 Planet（星球）联系。牢记「抗体就像是身体的士兵」。
10. Variation and Classification – Sorting Life | 变异与分类——给生命排序
Organisms show tremendous variation, both within and between species. Variation can be continuous (height, weight – any value within a range) or discontinuous (tongue rolling, blood group – distinct categories). Variation arises from genes, environment, or a mixture of both. Classification means grouping organisms based on shared features. The five kingdoms are Animals, Plants, Fungi, Prokaryotes (bacteria) and Protists. Within animals, vertebrates are divided into five classes: mammals, birds, reptiles, amphibians and fish. A good way to remember these five vertebrate groups is ‘My Best Rabbit Ate Flies’.
生物表现出巨大的变异，既存在于物种之间，也存在于物种之内。变异可以是连续变异（身高、体重——在范围内可取任意值）或不连续变异（卷舌、血型——截然不同的类别）。变异源于基因、环境或两者的混合。分类意味着根据共同特征对生物进行分组。五界系统为动物界、植物界、真菌界、原核生物界（细菌）和原生生物界。在动物中，脊椎动物分为五个纲：哺乳纲、鸟纲、爬行纲、两栖纲和鱼纲。记住这五类脊椎动物的好方法是「My Best Rabbit Ate Flies」（我最好的兔子吃了苍蝇）。
For continuous vs discontinuous, picture a graph: continuous gives a smooth bell curve, discontinuous gives separate bars. Remember the five kingdoms with ‘All Plants Find Pizza Perfect’ – Animals, Plants, Fungi, Prokaryotes, Protists. Use a dichotomous key to identify organisms by answering a series of yes/no questions – it works like a choose-your-own-adventure book.
对于连续和不连续变异，想象一张图：连续变异得到平滑的钟形曲线，不连续变异得到分开的柱状图。用「All Plants Find Pizza Perfect」记住五界——Animals（动物界）、Plants（植物界）、Fungi（真菌界）、Prokaryotes（原核生物界）、Protists（原生生物界）。使用二歧检索表通过回答一系列是/否问题来鉴别生物——它就像一本选择自己的冒险故事书。
11. Nutrient Cycles – Recycling Matter | 营养物质循环——物质的回收
Unlike energy, matter is constantly recycled in ecosystems. The carbon cycle shows how carbon moves between the atmosphere, living organisms and the Earth. Plants absorb CO₂ for photosynthesis; animals eat plants and release CO₂ by respiration. Decomposers like bacteria and fungi break down dead matter, returning carbon to the soil and air. Burning fossil fuels also releases carbon dioxide. The nitrogen cycle involves nitrogen-fixing bacteria in root nodules of leguminous plants (peas, beans) that convert atmospheric nitrogen into nitrates. Nitrates are taken up by plants to make proteins. Decomposers recycle nitrogen from waste and dead organisms back to the soil as ammonia, then nitrates.
与能量不同，物质在生态系统中不断循环。碳循环展示了碳在大气、生物体和地球之间的移动。植物吸收 CO₂ 进行光合作用；动物吃植物并通过呼吸作用释放 CO₂。细菌和真菌等分解者分解死去的生物体，将碳归还土壤和空气。燃烧化石燃料也会释放二氧化碳。氮循环涉及豆科植物（豌豆、大豆）根瘤中的固氮细菌，它们将大气中的氮转化为硝酸盐。植物吸收硝酸盐来制造蛋白质。分解者将来自废物和死生物的氮重新以氨的形式返回土壤，然后再变成硝酸盐。
Visualise the carbon cycle as a ‘See-Saw’ – CO₂ goes up with respiration and burning, down with photosynthesis. Think ‘Fix N₂ to NO₃⁻’ for nitrogen fixation. The role of decomposers is like nature’s recycling crew.
把碳循环想象成一个「翘翘板」——呼吸作用和燃烧使 CO₂ 上升，光合作用使其下降。对于固氮作用，记成「把 N₂ 固定为 NO₃⁻」。分解者的角色就像大自然的回收小队。
12. Scientific Investigations and Vocabulary | 科学探究与词汇
Biology is full of practical work, so you must be confident with terms like hypothesis (a testable prediction), independent variable (the one you change), dependent variable (the one you measure) and control variables (things you keep the same to make a fair test). Reliability comes from repeating measurements; accuracy means how close a reading is to the true value. Precision relates to the smallest scale division on a measuring instrument. When presenting data, plot a bar chart for categories or a line graph for continuous data. Always label axes and include units.
生物学充满了实践操作，因此你必须对以下术语有信心：假设（可测试的预测）、自变量（你改变的量）、因变量（你测量的量）和控制变量（为公平测试而保持不变的量）。可靠性来自重复测量；准确度指读数接近真实值的程度。精密度与测量仪器的最小刻度有关。展示数据时，类别数据使用条形图，连续数据使用折线图。一定要标记坐标轴并附上单位。
Use ‘Cows Moo Softly’ for Change, Measure, Same (independent, dependent, control). When analysing graphs, remember ‘D rop, I ncrease, P eak’ – describe what you see, give data (numbers), compare if needed, and explain.
用「Cows Moo Softly」记住Change（改变）、Measure（测量）、Same（保持不变）（自变量、因变量、控制变量）。分析图表时，记住「D.I.P.」——描述你所看到的、给出数据（数字）、必要时进行比较，并加以解释。
Published by TutorHao | Biology Revision Series | aleveler.com
更多咨询请联系16621398022（同微信）
或截图后用「扫一扫 → 相册」选择本图