📚 Year 9 CAIE Biology: A Fast-Track Guide to Mastering Key Terminology | Year 9 CAIE 生物：关键术语速记指南
Biology in Year 9 can feel like learning a new language, with dozens of unfamiliar terms appearing in every topic. This guide breaks down the most important CAIE terminology into paired English–Chinese explanations, complete with memory tricks and clear examples. By linking each scientific term to a vivid image or story, you will move from memorising to truly understanding the vocabulary that underpins every lesson.
Year 9 生物像在学说一门新语言，每个单元都会冒出几十个陌生术语。这份指南把 CAIE 最重要的词语拆成中英对照的解释，配上记忆窍门和清晰的例子。把每个科学名词和一个生动的画面或故事挂钩，你就能从死记硬背变成真正理解这些贯穿课堂的词汇。
1. Levels of Biological Organisation | 生物层次结构
Cell: The smallest unit of life that can carry out all life processes. Think of a single brick in a massive wall – it is the basic building block.
细胞： 能独立完成所有生命活动的最小单位。想象高墙中的一块砖 – 它就是最基本的构件。
Tissue: A group of similar cells working together to perform a shared function, just like a team of workers with the same skill set.
组织： 一群形态结构相似的细胞共同执行某一功能，好比拥有同样技能的一组工人协作。
Organ: A structure made of different tissues that carry out a specific job. The heart, for example, is a pump built from muscle tissue, nerve tissue and connective tissue.
器官： 由多种组织构成的能够执行特定功能的结构，例如心脏就是由肌肉组织、神经组织和结缔组织共同构成的“泵”。
Organ system: A group of organs that work together to perform a major function, such as the digestive system. Picture an assembly line where each machine has a distinct role.
器官系统： 多个器官协同完成一个主要生理功能，比如消化系统。可想象成一条流水线，每台机器各司其职。
Organism: A complete living individual made up of organ systems. You are an organism – the whole factory, not just one machine.
生物体： 由器官系统组成的完整的生命个体。你就是生物体 – 是整个工厂，而不只是一台机器。
2. Essential Cell Organelles | 核心细胞器
Nucleus: The control centre of the cell, containing DNA. Imagine the principal’s office where all the important blueprints are kept.
细胞核： 细胞的控制中心，内含遗传物质 DNA。想像成校长的办公室，存放着所有的设计蓝图。
Cytoplasm: The jelly-like substance filling the cell, where chemical reactions occur. It is the “factory floor” bustling with activity.
细胞质： 充满细胞的胶状物质，是化学反应发生的场所，就像忙碌的“厂房车间”。
Cell membrane: The partially permeable barrier that surrounds every cell, controlling what enters and exits. Picture a bouncer at a club who only lets the right guests through.
细胞膜： 包围细胞的半透性屏障，控制物质进出。就像夜店门卫，只允许特定的客人进入。
Mitochondria (singular: mitochondrion): The site of aerobic respiration, releasing energy. Think of them as tiny power stations scattered across the cell.
线粒体： 有氧呼吸发生的场所，释放能量。可看作分布在细胞内的微型发电站。
Chloroplast: Found only in plant cells, this organelle contains chlorophyll and is the site of photosynthesis. Imagine a solar panel that also builds sugar.
叶绿体： 仅存在于植物细胞中，含叶绿素，是光合作用的场所。想像一块既能捕获太阳能又能制作糖分的太阳能板。
3. Movement of Substances | 物质进出细胞
Diffusion: The net movement of particles from a region of higher concentration to a region of lower concentration – no energy is required. Picture a drop of ink slowly spreading through water until it is evenly dispersed.
扩散： 粒子从高浓度区域向低浓度区域的净移动，不需要能量。像一滴墨在水中慢慢散开，直到均匀分布。
Osmosis: The diffusion of water molecules through a partially permeable membrane from a dilute solution to a more concentrated one. Say “OSmosis is Only for Water,” to remember the key difference.
渗透： 水分子通过半透膜从低浓度溶液向高浓度溶液的扩散。记住“OSmosis只认水”，就不会混淆。
Active transport: The movement of particles against the concentration gradient, using energy from ATP. It is like swimming upstream or pushing a heavy box uphill.
主动运输： 粒子逆浓度梯度的移动，需要消耗来自 ATP 的能量。好比逆流游泳或把重箱子推上山坡。
4. Biological Molecules & Enzymes | 生物分子与酶
Carbohydrates: Molecules made of carbon, hydrogen and oxygen, used as the body’s main energy source. Simple sugars like glucose are the “instant fuel”; starch is the “stored fuel.”
碳水化合物： 由碳、氢、氧组成的分子，是身体主要能源。葡萄糖等单糖是“即时燃料”；淀粉则是“储备燃料”。
Proteins: Long chains of amino acids needed for growth and repair. Each protein has a unique shape – think of keys that fit only certain locks.
蛋白质： 由氨基酸组成的长链，用于生长和修复。每种蛋白质都有独特的形状 – 像只对特定锁孔的钥匙。
Lipids (fats): Energy-rich molecules that provide insulation and make up cell membranes. They can be remembered as “waterproof packaging and long-lasting fuel.”
脂类（脂肪）： 富含能量的分子，提供隔热并构成细胞膜。可以记作“防水包装兼长效燃料”。
Enzyme: A biological catalyst that speeds up chemical reactions without being used up. The active site is shaped exactly to fit the substrate, like a glove fitting a hand.
酶： 一种生物催化剂，能加速化学反应而自身不被消耗。活性位点的形状与底物恰好互补，像手套与手的贴合。
Denaturation: When an enzyme’s shape is permanently changed by extreme temperature or pH, the substrate can no longer fit. Picture melting a plastic key so it no longer opens the door.
变性： 极端温度或 pH 使酶的形状永久改变，底物再也无法结合。想像把一把塑料钥匙熔掉，门就打不开了。
5. Plant Nutrition & Photosynthesis | 植物营养与光合作用
Photosynthesis: The process by which plants use light energy to convert carbon dioxide and water into glucose and oxygen. The word equation sums it up: Carbon dioxide + Water → Glucose + Oxygen, in the presence of light and chlorophyll.
光合作用： 植物利用光能，将二氧化碳和水转化为葡萄糖和氧气的过程。文字方程式总结：二氧化碳 + 水 → 葡萄糖 + 氧气，需要光和叶绿素。
Chlorophyll: The green pigment in chloroplasts that absorbs sunlight. Without chlorophyll, a plant would be like a phone without a battery – it cannot capture energy.
叶绿素： 叶绿体内吸收阳光的绿色色素。没有叶绿素，植物就像没电的手机 – 无法捕获能量。
Limiting factor: Any environmental factor that slows down photosynthesis when it is in short supply, such as light intensity, carbon dioxide concentration or temperature. Think of a three-legged race: the slowest runner sets the pace.
限制因素： 供应不足时会减慢光合作用的任何环境因素，比如光照强度、二氧化碳浓度或温度。想像两人三足比赛：走得最慢的人决定了速度。
Balanced chemical summary: H₂O → C₆H₁₂O₆ + 6O₂. Notice how the atoms are rearranged; nothing is created or destroyed.
化学方程式小结： 6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂。注意原子的重新排列，物质既没有凭空产生也没有消失。
6. Human Nutrition & Digestion | 人类营养与消化
Digestion: The breakdown of large, insoluble food molecules into small, soluble molecules that can be absorbed into the blood. Mechanical digestion (chewing) is like tearing a book into pages; chemical digestion (enzymes) is like unzipping each sentence into words.
消化： 将大而不可溶的食物分子分解为小而可溶、能被血液吸收的分子。物理性消化（咀嚼）好比把一本书撕成散页；化学性消化（酶）则像是把句子的拉链拉开，变成一个个单词。
Absorption: The movement of digested food molecules through the wall of the intestine into the blood. Villi are tiny finger-like projections that increase the surface area, just like a super-absorbent sponge with millions of extra folds.
吸收： 已消化的小分子穿过肠壁进入血液的过程。小肠绒毛是微小的指状突起，大大增加了表面积，就像一块拥有数百万额外褶皱的超强吸水海绵。
Peristalsis: Waves of muscular contraction that squeeze food along the gut. Picture squeezing toothpaste through a tube – the muscles behind the bolus contract while those ahead relax.
蠕动： 肌肉收缩波推动食糜沿着消化道前进。想像挤牙膏：食团后方肌肉收缩，前方肌肉放松。
7. The Respiratory System & Cellular Respiration | 呼吸系统与细胞呼吸
Breathing (ventilation): The physical process of moving air in and out of the lungs. The diaphragm and intercostal muscles do the heavy lifting – inhale: diaphragm flattens; exhale: diaphragm relaxes.
呼吸（通气）： 空气进出肺部的物理过程。膈肌和肋间肌承担主要工作 – 吸气时膈肌变平，呼气时膈肌放松。
Alveoli (singular: alveolus): Tiny air sacs in the lungs where gas exchange occurs. Their walls are one cell thick and surrounded by capillaries, maximising diffusion – like thousands of delicate balloon clusters.
肺泡： 肺内微小的气囊，气体交换在此进行。其壁仅一个细胞厚，周围密布毛细血管，最大化扩散效率 – 像数千簇精巧的气球串。
Aerobic respiration: The release of energy from glucose using oxygen. Equation: Glucose + Oxygen → Carbon dioxide + Water (+ energy). It is the preferred, high-yield energy pathway.
有氧呼吸： 利用氧气从葡萄糖中释放能量。方程式：葡萄糖 + 氧气 → 二氧化碳 + 水 (+ 能量)。这是最优选的高产能途径。
Anaerobic respiration: The release of energy from glucose without oxygen, producing less energy and, in animals, lactic acid. This is the emergency backup generator – powerful but short-lived and messy.
无氧呼吸： 在没有氧气的情况下从葡萄糖释放能量，产能更少，动物会生成乳酸。这是应急备用发电机 – 强劲但短暂且会留下一片狼藉。
8. The Circulatory System | 循环系统
Double circulation: In mammals, blood passes through the heart twice in one complete circuit – once to the lungs and once to the rest of the body. Remember “two passports,” one for the pulmonary route and one for the systemic route.
双循环： 哺乳动物血液在一次完整的循环中两次经过心脏 – 一次去肺，一次去身体其他部分。可记作“双护照”，肺循环一本、体循环一本。
Arteries: Thick-walled, muscular vessels that carry blood away from the heart. They handle high pressure, so the wall is strong. Think “A for Away” and “A for Arteries.”
动脉： 壁厚且有弹性的血管，将血液带离心脏。它们承受高压，因此管壁结实。记住“A 代表 away（远离）”。
Veins: Thinner-walled vessels that carry blood back to the heart. They contain valves to prevent backflow, like one-way swing doors.
静脉： 管壁较薄的血管，将血液带回心脏。它们有瓣膜防止倒流，像单向旋转门。
Capillaries: Microscopic vessels with walls one cell thick, linking arteries and veins. This is the exchange zone where oxygen and nutrients are delivered. Their thin walls are the ultimate negotiation table.
毛细血管： 管壁仅一个细胞厚的微型血管，连接动脉和静脉。这里是氧气和营养物质交换区域，其薄壁就像是最高效的谈判桌。
9. Immune System & Disease | 免疫与疾病
Pathogen: cterium, fungus or protist. You can remember “pathogen = pathology generator.”
病原体： 引起疾病的微生物，如病毒、细菌、真菌或原虫。可以记作“病原体 = 疾病发生器”。
Phagocyte: A white blood cell that engulfs and digests pathogens – a loyal “Pac-Man” of the immune system.
吞噬细胞： 一种能吞噬并消化病原体的白血球 – 免疫系统里忠诚的“吃豆人”。
Lymphocyte: A white blood cell that produces specific antibodies to disable pathogens. Each lymphocyte is a precision sniper, custom-making bullets that only fit one target.
淋巴细胞： 产生特异性抗体使病原体失活的白血球。每个淋巴细胞好比精密狙击手，定制只适合一个靶标的子弹。
Vaccination: Introducing a harmless form of a pathogen to stimulate the immune system to produce memory cells. It is a dress rehearsal for your body’s defence force.
疫苗接种： 引入无害形式的病原体，刺激免疫系统产生记忆细胞。这是为身体防御部队安排的彩排。
10. Reproduction in Plants | 植物繁殖
Pollination: The transfer of pollen from the anther to the stigma. Wind-pollinated flowers often lack bright petals, while insect-pollinated ones advertise colour and scent. Think “Pollen on a Postman” – either wind or insect.
传粉： 花粉从花药传到柱头的过程。风媒花常缺少鲜艳花瓣，而虫媒花则以颜色和气味招客。想象“花粉快递员”，不是风就是虫。
Fertilisation (in plants): The fusion of a male gamete (pollen nucleus) with a female gamete (ovule) to form a zygote. After this, the ovule becomes a seed and the ovary often becomes fruit.
受精（植物）： 雄配子（花粉核）与雌配子（胚珠）融合形成合子的过程。之后，胚珠发育为种子，子房通常发育为果实。
Seed dispersal: The spreading of seeds away from the parent plant to reduce competition. Methods include wind, water, animals and explosive mechanism – each is a different delivery service.
种子传播： 将种子散布到远离母株的地方以减少竞争。方式包括风播、水播、动物传播和弹射传播，每一种都是不同的投递服务。
11. Reproduction in Humans | 人类生殖
Gamete: A sex cell – sperm in males, egg (ovum) in females – containing half the number of chromosomes. Sperm are tiny motile messengers; the egg is a large, resource-rich target cell.
配子： 性细胞 – 雄性为精子，雌性为卵子 – 含有染色体数目的一半。精子是微小能动的信使；卵子是体积较大、资源丰富的靶细胞。
Fertilisation (in humans): The fusion of sperm nucleus and egg nucleus in the oviduct, restoring the full chromosome number. It marks the starting whistle of a complex developmental race.
受精（人类）： 精核与卵核在输卵管内融合，恢复全部染色体数目。这吹响了复杂发育赛程的出发哨。
Placenta: The disc-shaped organ that anchors the embryo to the uterine wall, allowing exchange of oxygen, nutrients and wastes without mixing maternal and fetal blood. Think of it as a highly selective customs and delivery hub.
胎盘： 将胚胎固定在子宫壁上的盘状器官，允许氧气、营养物质和废物的交换但又使母血和胎血不混合。想像成一个高度选择性的海关兼快递中心。
Gestation: The period of development inside the uterus, lasting about 40 weeks in humans. It is the construction phase – foundation to final fittings.
妊娠期： 在子宫内发育的时段，人类约持续 40 周。这是建筑工程阶段 – 从地基到最后的装修。
12. Ecosystems & Energy Flow | 生态系统与能量流动
Ecosystem: A community of living organisms interacting with each other and their non-living environment. Visualise every actor and the stage they perform on together.
生态系统： 生物群落与其非生物环境相互作用形成的整体。把它想象成全体演员和他们共同表演的舞台。
Producer: An organism that makes its own food using energy from the sun (e.g., green plants). Producers are the battery packs of every food chain.
生产者： 能利用太阳光制造养分的生物（如绿色植物）。生产者是每条食物链的电池包。
Consumer: An organism that obtains energy by eating other organisms. Primary consumers eat plants, secondary consumers eat primary consumers – each step is a link in the energy relay.
消费者： 通过取食其他生物获取能量的生物。初级消费者吃植物，次级消费者吃初级消费者 – 每一步都是能量接力中的一棒。
Decomposer: A microorganism that breaks down dead organic matter, returning nutrients to the soil. Without decomposers, the world would be buried in un-recycled remains – nature’s cleanup crew.
分解者： 分解死亡有机物的微生物，将养分归还土壤。没有分解者，世界将被未回收的残骸掩埋 – 它们是大自然的清洁队。
Trophic level: The position an organism occupies in a food chain. Energy is lost at each level, so the pyramid stands on a broad producer base. Pyramid diagrams help visualise this flow.
营养级： 生物在食物链中所处的位置。能量在每一级都有损耗，所以金字塔坐落于宽阔的生产者基层之上。金字塔图直观展示了这种流动。
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