📚 A Comprehensive Guide to the Year 12 WJEC Biology Syllabus | Year 12 WJEC 生物：课程大纲全面解析
WJEC is a leading UK examination board that offers A-level Biology tailored to the Welsh curriculum. Year 12 WJEC Biology forms the AS component, covering fundamental concepts from biomolecules and cell structure to whole-organism physiology and biodiversity. Understanding this syllabus in depth is the first step toward success, whether you are aiming for a high AS grade or building a foundation for the full A-level.
WJEC 是英国主流考试局之一，为威尔士课程量身打造 A-Level 生物学。Year 12 WJEC 生物学属于 AS 阶段，涵盖从生物分子、细胞结构到整体生理学与生物多样性的基础内容。深入掌握这份课程大纲是迈向成功的第一步，无论你志在取得 AS 高分，还是为完整的 A-Level 打下根基。
1. WJEC Year 12 Biology at a Glance | Year 12 生物课程总览
The Year 12 WJEC Biology specification is divided into two examined units and a practical skills endorsement. Unit 1 focuses on Basic Biochemistry and Cell Organisation, while Unit 2 covers Biodiversity and Physiology of Body Systems. Both examinations are taken at the end of the academic year, each lasting 1 hour 30 minutes and carrying equal weighting toward the AS qualification. A strong performance in Year 12 also contributes to your UCAS predicted grades.
Year 12 WJEC 生物学大纲分为两个笔试单元以及一项实验技能认可。第一单元侧重于基础生物化学与细胞组织，第二单元涵盖生物多样性与身体系统生理学。两场考试均在学年末进行，各为 1 小时 30 分钟，并在 AS 资格中权重相同。Year 12 的优异表现还会影响你的 UCAS 预估成绩。
2. Unit 1 Core Concepts: Biochemistry | 第一单元核心概念：生物化学
Unit 1 begins with the chemistry of life. You will study the structure and properties of water, the roles of monosaccharides, disaccharides and polysaccharides (e.g., starch, glycogen, cellulose), the nature of triglycerides and phospholipids, and the levels of protein structure. Biochemical tests for reducing and non-reducing sugars, starch, proteins and lipids are also required practical skills.
第一单元从生命化学开始。你将学习水的结构与性质，单糖、二糖和多糖（如淀粉、糖原、纤维素）的作用，甘油三酯和磷脂的特性，以及蛋白质的各级结构。还原糖与非还原糖、淀粉、蛋白质和脂质的生化检测也是必考的实验技能。
The properties of water – high specific heat capacity, cohesion, adhesion and its role as a solvent – underpin its biological significance. You need to relate these properties to processes such as transpiration and temperature regulation.
水的特性——高比热容、内聚力、附着力和作为溶剂的作用——奠定了其生物意义。你需要将这些特性与蒸腾作用和体温调节等过程联系起来。
3. Cell Structure, Organelles and Microscopy | 细胞结构、细胞器与显微镜
You must be able to describe the ultrastructure of eukaryotic and prokaryotic cells, including the functions of organelles such as the nucleus, mitochondria, ribosomes, endoplasmic reticulum, Golgi apparatus and lysosomes. A comparison between plant and animal cells, as well as the unique features of prokaryotic cells, is essential.
你需要描述真核和原核细胞的超微结构，包括细胞核、线粒体、核糖体、内质网、高尔基体和溶酶体等细胞器的功能。动植物细胞比较以及原核细胞的独特特征也是必考内容。
The use of light and electron microscopes, calculation of magnification and actual size, and cell fractionation techniques form the experimental spine of this topic. Grasping the principles of resolution and the limitations of each microscope type helps you interpret ultrastructural images accurately.
光学和电子显微镜的使用、放大倍率与实际尺寸的计算以及细胞分级分离技术构成了本主题的实验基础。掌握分辨率原理和各型显微镜的局限性，有助于准确解读超微图像。
4. Membrane Structure and Cellular Transport | 膜结构与细胞运输
The fluid mosaic model of membrane structure is a key concept. You will explore the roles of phospholipids, cholesterol, intrinsic and extrinsic proteins, and glycoproteins. The processes of diffusion, facilitated diffusion, osmosis, active transport, endocytosis and exocytosis are all tested.
膜的流体镶嵌模型是关键概念。你将探索磷脂、胆固醇、内在蛋白与外在蛋白以及糖蛋白的作用。扩散、协助扩散、渗透、主动运输、胞吞和胞吐等过程都属于考查范围。
Water potential and its role in plant and animal cells are particularly relevant for explaining plasmolysis and turgor. The effects of placing cells in hypotonic, isotonic and hypertonic solutions must be understood at a molecular level.
水势及其在动植物细胞中的作用对于解释质壁分离和膨压尤为重要。必须从分子层面理解将细胞置于低渗、等渗和高渗溶液中的影响。
5. Enzymes, Nucleic Acids and Cell Division | 酶、核酸与细胞分裂
Enzyme structure, specificity, the induced-fit model and factors affecting enzyme activity (temperature, pH, substrate concentration, inhibitors) are core. Understanding competitive and non-competitive inhibition using graphs is often examined. The structure of DNA (double helix, antiparallel strands, complementary base pairing) and RNA, as well as semi-conservative DNA replication, are covered.
酶的结构、专一性、诱导契合模型以及影响酶活性的因素（温度、pH、底物浓度、抑制剂）是核心。利用图表分析竞争性和非竞争性抑制是常见考点。DNA（双螺旋、反向平行链、互补碱基配对）和 RNA 的结构以及半保留复制也涵盖在内。
Cell division includes the stages of mitosis (prophase, metaphase, anaphase, telophase) and its significance in growth, repair and asexual reproduction. You should also recognise the behaviour of chromosomes and the role of the spindle fibres.
细胞分裂包括有丝分裂各阶段（前期、中期、后期、末期）及其在生长、修复和无性繁殖中的意义。你还应识别染色体的行为以及纺锤丝的作用。
| Enzyme Inhibition Types 酶抑制类型 | |
|---|---|
| Competitive: inhibitor resembles substrate and binds to active site; effect can be overcome by increasing substrate concentration. | 竞争性：抑制剂与底物相似，结合活性位点；增加底物浓度可克服作用。 |
| Non-competitive: inhibitor binds to an allosteric site, altering active site shape; increasing substrate concentration does not reverse inhibition. | 非竞争性：抑制剂结合别构位点，改变活性位点形状；增加底物浓度无法逆转抑制。 |
6. Unit 2: Exploring Biodiversity | 第二单元：探索生物多样性
Unit 2 shifts focus to the diversity of life. You will learn about the principles of classification (taxonomy, hierarchical system, binomial naming), the five-kingdom system, and the key features of the domains. Biodiversity can be assessed using species richness, Simpson's Diversity Index, and genetic diversity.
第二单元转向生命多样性。你将学习分类原则（分类学、层级系统、双名法）、五界系统以及各域的关键特征。生物多样性可通过物种丰富度、辛普森多样性指数和遗传多样性来评估。
Fieldwork techniques like random sampling (quadrat, transect) are essential for practical skills assessment. Understanding the ecological factors that influence distribution and abundance helps you design valid surveys and calculate diversity indices accurately.
随机取样（样方、样条）等野外调查技术是实验技能评估的重要部分。理解影响分布和多度的生态因子，有助于你设计有效的调查并精确计算多样性指数。
7. Gas Exchange and Circulatory Systems | 气体交换与循环系统
The syllabus covers respiratory systems in fish (gills, countercurrent flow), insects (tracheal system) and mammals. You must detail the structure of the human gas exchange system, including the trachea, bronchi, bronchioles and alveoli. The mechanism of ventilation (inspiration and expiration) is examined.
大纲涵盖鱼类（鳃、逆流交换）、昆虫（气管系统）和哺乳动物的呼吸系统。你需要详细说明人体气体交换系统的结构，包括气管、支气管、细支气管和肺泡。通气机制（吸气和呼气）也是考点。
Circulatory systems compared: open vs closed, single vs double circulation. The structure of the heart, the cardiac cycle, and the role of arteries, veins and capillaries are central. You should be able to interpret ECG traces and pressure changes in the heart.
循环系统对比：开放与闭锁循环、单与双循环。心脏结构、心动周期以及动脉、静脉和毛细血管的作用是核心内容。你应能够解读心电图图线以及心脏内压力变化。
8. Digestion, Adaptation and Transport in Plants | 消化、适应与植物运输
In mammals, you will explore the digestive system, the action of enzymes (amylase, proteases, lipase), absorption of nutrients, and the remarkable adaptation of the small intestine. Adaptations of organisms to their environment, such as extremophiles and body shape, are also studied.
在哺乳动物中，你将探索消化系统、酶的作用（淀粉酶、蛋白酶、脂肪酶）、营养物质的吸收以及小肠的显著适应。生物对其环境的适应，如嗜极生物与体型，也是学习内容。
Plant biology includes the structure of xylem and phloem, the cohesion-tension theory of water transport, and translocation of organic solutes (mass flow hypothesis). You need to link transpiration to environmental factors and explain how companion cells assist loading of sucrose.
植物生物学包括木质部和韧皮部的结构，水分运输的凝聚力-张力理论，以及有机溶质的转运（集流假说）。你需要将蒸腾作用与环境因素联系起来，并解释伴胞如何协助加载蔗糖。
9. Immune System and Disease | 免疫系统与疾病
The non-specific and specific immune responses are key. You will study phagocytosis, T lymphocytes (helper and cytotoxic), B lymphocytes, antibody structure and function, and the differences between cell-mediated and humoral immunity. Vaccination, passive and active immunity, and the development of autoimmune diseases or allergies are examinable.
非特异性与特异性免疫反应是关键。你将学习吞噬作用、T 淋巴细胞（辅助性和细胞毒性）、B 淋巴细胞、抗体结构与功能，以及细胞免疫与体液免疫的差异。疫苗接种、被动与主动免疫，以及自身免疫病或过敏的产生也是考查内容。
The role of memory cells in long-term protection and the ethical issues surrounding vaccine programmes offer opportunities for extended responses. Understanding how HIV affects the immune system is a frequently tested application.
记忆细胞在长期保护中的作用以及围绕疫苗计划的伦理问题，为拓展答题提供了机会。理解 HIV 如何影响免疫系统是常考的应用内容。
10. Assessment Details and Practical Skills | 评估细节与实验技能
The AS qualification comprises Unit 1 (1h30, 20% of A-level), Unit 2 (1h30, 20% of A-level), and a practical skills endorsement. Paper 1 assesses topics 1–5 (biochemistry, cell organisation), while Paper 2 assesses topics 6–10 (biodiversity, physiology). Both include short-answer and extended response questions.
AS 资格包括第一单元（1小时30分，占 A-level 的20%）、第二单元（同上）和实验技能认可。试卷一考查主题1-5（生物化学、细胞组织），试卷二考查主题6-10（生物多样性、生理学）。两卷均包含简答与拓展题。
Your teacher will continually assess practical competency through designated experiments, covering microscopy, biochemical tests, enzyme kinetics, transport and field sampling. Keep a well-organised lab book and practise data analysis, as numerical skills count for a significant portion of the marks.
教师将通过指定实验持续评估你的实验能力，涵盖显微镜、生化检测、酶动力学、运输和野外取样等。请保持实验记录本井然有序并勤练数据分析，因为计算技能在分数中占相当比重。
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