High School Biology

Human Anatomy and Physiology人体解剖与生理学

The human body is built from cells organized into tissues, organs, and organ systems — each system specialized for a distinct function yet intimately connected with all others. This guide covers the seven core systems: the digestive system (nutrient uptake), the circulatory system (transport), the respiratory system (gas exchange), the nervous system (control and signaling), the immune system (defense), and an overview of the endocrine and reproductive systems (chemical control and continuation of the species). Every section maps to your curriculum, from NGSS systems-model expectations through Ontario SBI3U Strand E and the rich system-by-system depth of BC Anatomy and Physiology 12.人体由细胞组成，细胞构成组织（tissue，组织），组织构成器官（organ，器官），器官组成系统（system，系统）——每个系统各有专司，却又紧密相连。本指南涵盖七大核心系统：消化系统（digestive system，消化系统）负责营养摄取，循环系统（circulatory system，循环系统）负责物质运输，呼吸系统（respiratory system，呼吸系统）负责气体交换，神经系统（nervous system，神经系统）负责控制与信号传递，免疫系统（immune system，免疫系统）负责防御，以及内分泌系统（endocrine system，内分泌系统）与生殖系统概述。所有内容均与各大纲对应，从 NGSS 系统模型要求到安大略 SBI3U E 单元，再到 BC 解剖与生理 12 的系统逐一深入。

7 sections7 节内容 US NGSS · ON · BC · ABUS NGSS · ON · BC · AB BC A&P 12 system depth marked HonorsBC 解剖与生理 12 系统深度标为荣誉级
Read me first先读这里

How to use this guide如何使用本指南

Human Anatomy and Physiology sits in every biology curriculum mapped here, but the depth and system selection vary sharply. NGSS treats all organ systems through the single HS-LS1-2 hierarchical-organization model and one homeostasis investigation PE (HS-LS1-3) — it has no dedicated system-by-system expectation. Ontario SBI3U Strand E requires detailed anatomy of the respiratory, circulatory, and digestive systems, plus disorders. Ontario SBI4U Strand E adds the endocrine, excretory, and nervous systems with their homeostatic feedback loops — the harder Grade-12 track. British Columbia Anatomy and Physiology 12 is the richest of the four: all eight organ systems with structural and functional interdependence and homeostasis framing. Alberta Biology 20 Unit D covers digestive, respiratory, circulatory, and defence systems at Grade 11; the nervous and endocrine systems are deferred to Biology 30 Unit A (Grade 12). The table below locates each section in your curriculum.人体解剖与生理学存在于我们对照的所有生物大纲中，但深度和系统选择差异显著。NGSS 通过单一的 HS-LS1-2 层级组织模型和一项稳态调查表现期望（HS-LS1-3）涵盖所有器官系统——没有专门的逐系统期望。安大略 SBI3U E 单元要求详细掌握呼吸、循环和消化系统的解剖，以及相关疾病。安大略 SBI4U E 单元增加内分泌、排泄和神经系统及其稳态反馈回路——这是较难的 12 年级轨道。不列颠哥伦比亚解剖与生理 12 是四套大纲中最丰富的：涵盖全部八大器官系统，并涉及结构与功能的相互依存及稳态框架。阿尔伯塔 Biology 20 D 单元在 11 年级涵盖消化、呼吸、循环和防御系统；神经和内分泌系统推迟至 Biology 30 A 单元（12 年级）。下表定位各节在你大纲中的位置。

If you are in…如果你在… Focus on these sections重点学习 Defer / lighter可推迟 / 减负 Source依据
🇺🇸 US NGSS HS Life Sciences美国 NGSS 生命科学 §1 (levels of organization — the HS-LS1-2 systems model); cram-cheat boxes for big-picture function of each system§1（生命组织层次——HS-LS1-2 系统模型）；各系统速记框了解大图景功能 Named structural detail (valve types, reflex arcs, named hormones) — NGSS Assessment Boundary excludes molecular/reaction level命名结构细节（瓣膜类型、反射弧、特定激素）——NGSS 评估边界排除分子/反应层面 NGSS HS Life Science — HS-LS1-2 and HS-LS1-3— HS-LS1-2 和 HS-LS1-3
🇨🇦 ON Grade 11 — SBI3U安大略 11 年级 — SBI3U §1 (levels), §2 (digestive), §3 (circulatory), §4 (respiratory) in full — E3.1, E3.2, E3.3 anatomy and disorder content§1（层次）、§2（消化）、§3（循环）、§4（呼吸）全部学习 —— E3.1、E3.2、E3.3 解剖及疾病内容 Endocrine, nervous, and reproductive going-deeper detail (§5, §7 honors) — these are SBI4U E3.1/E3.2, not SBI3U内分泌、神经与生殖深入内容（§5、§7 荣誉级）——属 SBI4U E3.1/E3.2，非 SBI3U Ontario SBI3U/4U Biology — SBI3U Strand E E3.1–E3.3— SBI3U E 单元 E3.1–E3.3
🇨🇦 ON Grade 12 — SBI4U Honors安大略 12 年级 — SBI4U 荣誉 All 7 sections in full, including nervous system action-potential signaling, endocrine feedback loops, and reproductive hormone cycles — E3.1, E3.2, E3.3全部 7 节完整学习，含神经系统动作电位信号、内分泌反馈回路和生殖激素周期 —— E3.1、E3.2、E3.3 Nothing — all systems connect to SBI4U Homeostasis (Strand E) and Metabolic Processes (Strand C)无 ——所有系统均与 SBI4U 稳态（E 单元）和代谢过程（C 单元）相关 Ontario SBI3U/4U Biology — SBI4U Strand E E3.1, E3.2, E3.3— SBI4U E 单元 E3.1、E3.2、E3.3
🇨🇦 BC A&P 12 HonorsBC 解剖与生理 12 荣誉 All 7 sections at full structural and functional depth — Big Idea 3: "Organ systems have complex interrelationships to maintain homeostasis." All eight named systems with interdependence全部 7 节结构与功能完整深度 ——大概念 3："器官系统具有复杂的相互关系以维持稳态。"全部八大系统及其相互依存 Nothing — BC A&P 12 is the deepest of the four curricula for human physiology无 ——BC 解剖与生理 12 是四套大纲中人体生理深度最高的 BC Life Sciences 11 / Anatomy 12 — A&P 12 Big Idea 3 + Organ systems Content—解剖与生理 12 大概念 3 + 器官系统内容
🇨🇦 AB Biology 20 / 30阿尔伯塔 Biology 20 / 30 Biology 20: §1, §2, §3, §4, §6 (Unit D: digestive, respiratory, circulatory, defence). Biology 30: §5, §7 nervous and endocrine (Unit A GO1/GO2) Honors Biology 30Biology 20：§1、§2、§3、§4、§6（D 单元：消化、呼吸、循环、防御）。Biology 30：§5、§7 神经与内分泌（A 单元 GO1/GO2）荣誉 Biology 30 Endocrine and reproductive hormone cycles (§7 honors) — defer to Biology 30 Unit A GO2 and Unit B内分泌与生殖激素周期（§7 荣誉级）——推迟至 Biology 30 A 单元 GO2 和 B 单元 Alberta Biology 20/30 — Bio 20 Unit D GO1–GO4; Bio 30 Unit A GO1–GO2— Bio 20 D 单元 GO1–GO4；Bio 30 A 单元 GO1–GO2

Once you have located your row, use the two cards below for the approach that fits your timeline.找到所在行后，用下面两张卡片选择适合你时间安排的方式。

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If you are cramming the night before如果你在临阵磨枪

Know the hierarchy (cell → tissue → organ → organ system → organism). For each system: name its main organ, its primary function, and one disorder. Read every cram-cheat box. For NGSS, focus on the systems-model framing (HS-LS1-2) rather than named structural detail. Skip the honors going-deeper sections unless you are in SBI4U or BC A&P 12.掌握层次（细胞 → 组织 → 器官 → 器官系统 → 生物体）。对每个系统：说出其主要器官、主要功能和一种疾病。读每个速记框。NGSS 学生聚焦系统模型框架（HS-LS1-2）而非命名结构细节。跳过荣誉深入内容，除非你在 SBI4U 或 BC 解剖与生理 12。

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If you are going for the top mark如果你目标顶分

Trace the path of a nutrient (mouth → esophagus → stomach → small intestine → blood), a breath (atmosphere → trachea → bronchioles → alveoli → blood), and a nerve impulse (receptor → afferent neuron → CNS → efferent neuron → effector). Link systems: the circulatory system connects every other system by delivering oxygen, hormones, and nutrients while removing wastes. Know at least one negative feedback loop (e.g. body temperature regulation) and how the endocrine and nervous systems cooperate to maintain it.追踪营养物质的路径（口腔 → 食道 → 胃 → 小肠 → 血液）、一次呼吸（大气 → 气管 → 细支气管 → 肺泡 → 血液）和一个神经冲动（感受器 → 传入神经元 → 中枢神经系统 → 传出神经元 → 效应器）。联系各系统：循环系统通过输送氧气、激素和营养并带走废物来连接其他所有系统。至少掌握一个负反馈回路（如体温调节），以及内分泌和神经系统如何协同维持稳态。

Honors flag.荣誉级标记。 Sections with going-deeper content on the nervous system (action potential, reflex arcs, CNS/PNS anatomy — §5), the endocrine system (named glands, feedback loops — §7), and the reproductive system (hormone cycles — §7) carry the Honors chip. These sections match Ontario SBI4U Strand E E3.1/E3.2, BC Anatomy & Physiology 12, and Alberta Biology 30 Unit A. If your curriculum is NGSS or SBI3U, read these sections for the big picture but do not memorize the named mechanisms.神经系统深入内容（动作电位、反射弧、中枢/外周神经系统解剖——§5）、内分泌系统（命名腺体、反馈回路——§7）和生殖系统（激素周期——§7）的深入内容标注 荣誉。这些内容对应安大略 SBI4U E 单元 E3.1/E3.2、BC 解剖与生理 12 和阿尔伯塔 Biology 30 A 单元。若你的大纲是 NGSS 或 SBI3U，阅读这些部分了解大图景，但无需记忆命名机制。
Section 1 · Levels of organization第 1 节 · 生命组织层次

Levels of Organization: From Cell to Organism生命组织层次：从细胞到生物体

The structural hierarchy underlying all human anatomy (NGSS HS-LS1-2; BC Life Sciences 11 Content; SBI3U Big Idea).人体解剖学的结构层次（NGSS HS-LS1-2；BC Life Sciences 11 内容；SBI3U 大观念）。
  1. Cell — the basic structural and functional unit of all life. In the human body, there are over 200 specialized cell types (e.g. red blood cells, neurons, muscle cells).细胞 — 一切生命的基本结构与功能单位。人体有超过 200 种特化细胞类型（如红细胞、神经元、肌肉细胞）。
  2. Tissue — a group of similar cells performing the same function. Four tissue types in animals: epithelial (covering/lining), connective (support/binding), muscle (contraction), nervous (signaling).组织 — 执行相同功能的同类细胞群。动物有四种组织类型：上皮组织（覆盖/内衬）、结缔组织（支撑/连接）、肌肉组织（收缩）、神经组织（信号传导）。
  3. Organ — two or more tissue types working together for a common function. E.g. the stomach contains epithelial, muscle, connective, and nervous tissue.器官 — 两种或多种组织共同完成某种功能。如胃含有上皮、肌肉、结缔和神经组织。
  4. Organ system — organs working together for a broad function. E.g. the digestive system (stomach + intestines + liver + pancreas) processes food and absorbs nutrients.器官系统 — 器官共同完成某种宏观功能。如消化系统（胃 + 肠 + 肝脏 + 胰腺）处理食物并吸收营养。
  5. Organism — the complete individual, whose organ systems interact to maintain life and homeostasis.生物体 — 完整的个体，其器官系统相互作用以维持生命和稳态。

The eight human organ systems and their primary function (BC A&P 12 Content): digestive (nutrient uptake), cardiovascular/circulatory (transport), respiratory (gas exchange), nervous (control), endocrine (chemical signaling), immune/lymphatic (defense), urinary (waste removal), reproductive (continuation of the species).人体八大器官系统及其主要功能（BC 解剖与生理 12 内容）：消化系统（营养摄取）、心血管/循环系统（物质运输）、呼吸系统（气体交换）、神经系统（控制）、内分泌系统（化学信号传导）、免疫/淋巴系统（防御）、泌尿系统（废物排除）、生殖系统（种族延续）。

NGSS HS-LS1-2 model expectation.NGSS HS-LS1-2 模型期望。

"Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms." The Clarification Statement specifies system-level functions: nutrient uptake, water delivery, movement in response to neural stimuli. An example: an artery depends on elastic tissue and smooth muscle to regulate blood delivery in the circulatory system. The Assessment Boundary explicitly excludes molecular or chemical reaction level interactions."建立并使用模型，说明多细胞生物体内为特定功能服务的相互作用系统的层级组织。"说明声明指定系统层面的功能：营养摄取、水分输送、响应神经刺激的运动。示例：动脉依赖弹性组织和平滑肌调节循环系统中的血液输送。评估边界明确排除分子或化学反应层面的互动。

The stomach contains epithelial tissue, muscle tissue, connective tissue, and nervous tissue working together. The stomach is therefore an example of which level of biological organization?胃含有上皮组织、肌肉组织、结缔组织和神经组织共同工作。因此胃是哪个生命组织层次的例子？
§1 · Q1
Tissue组织
Organ system器官系统
Organ器官
Cell细胞
An organ is defined as two or more tissue types working together for a common function. The stomach is an organ within the digestive system (an organ system). A tissue is a single cell type; an organ system is a collection of organs.器官定义为两种或多种组织类型共同完成某种功能。胃是消化系统（一个器官系统）中的器官。组织是单一细胞类型；器官系统是器官的集合。
An organ consists of multiple tissue types working together. A tissue is a single cell type; an organ system is a group of organs. The stomach, containing four tissue types, is an organ.器官由多种组织类型共同工作构成。组织是单一细胞类型；器官系统是器官的集合。含有四种组织类型的胃是器官。
Which of the four animal tissue types is primarily responsible for electrical signal transmission throughout the body?四种动物组织类型中，哪种主要负责在全身传递电信号？
§1 · Q2
Epithelial tissue上皮组织
Nervous tissue神经组织
Muscle tissue肌肉组织
Connective tissue结缔组织
Nervous tissue (neurons and supporting glial cells) is specialized for generating and transmitting electrical signals (action potentials). Epithelial tissue lines surfaces; connective tissue provides support and binding; muscle tissue contracts.神经组织（神经元和支持性神经胶质细胞）专门产生和传递电信号（动作电位）。上皮组织覆盖表面；结缔组织提供支撑和连接；肌肉组织收缩。
Nervous tissue is the signal-transmission tissue. Epithelial tissue covers/lines surfaces; connective tissue (bone, blood, cartilage) supports; muscle tissue contracts for movement.神经组织是信号传递组织。上皮组织覆盖/内衬表面；结缔组织（骨骼、血液、软骨）提供支撑；肌肉组织收缩产生运动。
Section 2 · The digestive system第 2 节 · 消化系统

The Digestive System消化系统

Path of food and the organs that process it (SBI3U E3.2; AB Biology 20 D GO1; BC A&P 12 Organ systems).食物路径及处理食物的器官（SBI3U E3.2；AB Biology 20 D GO1；BC 解剖与生理 12 器官系统）。
  1. Mouth: mechanical digestion (chewing / mastication) and salivary amylase begins chemical digestion of starch.口腔：机械消化（咀嚼）及唾液淀粉酶开始化学消化淀粉。
  2. Esophagus: muscular tube connecting mouth to stomach; peristalsis propels food downward.食道：连接口腔和胃的肌肉管；蠕动将食物向下推进。
  3. Stomach: churns food mechanically; secretes gastric acid (HCl) and pepsin to begin protein digestion. Sphincters control entry (cardiac) and exit (pyloric).胃：机械搅拌食物；分泌胃酸（盐酸）和胃蛋白酶开始蛋白质消化。括约肌控制食物进入（贲门）和排出（幽门）。
  4. Small intestine: most chemical digestion and nutrient absorption. Pancreatic enzymes (protease, lipase, amylase) and bile (from liver/gallbladder, emulsifies fat) act here. Villi and microvilli maximize surface area for absorption into the bloodstream.小肠：主要化学消化和营养吸收场所。胰酶（蛋白酶、脂肪酶、淀粉酶）和胆汁（来自肝脏/胆囊，乳化脂肪）在此发挥作用。绒毛和微绒毛最大化吸收表面积，将营养物质吸收入血液。
  5. Large intestine: reabsorbs water and electrolytes; compacts undigested material into feces for elimination.大肠：重新吸收水分和电解质；将未消化物质压缩为粪便排出体外。

Accessory organs: liver (bile production, detoxification), gallbladder (bile storage), pancreas (enzymes + insulin/glucagon hormones).附属器官：肝脏（产生胆汁、解毒）、胆囊（储存胆汁）、胰腺（酶 + 胰岛素/胰高血糖素激素）。

Worked Example 1 · Tracing nutrient absorption例题 1 · 追踪营养物质吸收

A student eats a meal containing bread (starch), chicken (protein), and butter (fat). For each macronutrient, state where chemical digestion begins, the enzyme responsible, and where absorption into the bloodstream primarily occurs.一名学生进食一顿含有面包（淀粉）、鸡肉（蛋白质）和黄油（脂肪）的餐食。对每种大量营养素，说明化学消化开始的位置、所用酶，以及主要吸收入血液的场所。

Starch (carbohydrate):淀粉（碳水化合物）： Digestion begins in the mouth (salivary amylase → maltose). Continues in the small intestine (pancreatic amylase). Final products (glucose) absorbed in the small intestine into capillaries.消化在口腔开始（唾液淀粉酶 → 麦芽糖），在小肠继续（胰淀粉酶）。最终产物（葡萄糖）在小肠吸收入毛细血管。

Protein:蛋白质： Digestion begins in the stomach (pepsin). Continues in the small intestine (pancreatic proteases). Final products (amino acids) absorbed in the small intestine into capillaries.消化在胃中开始（胃蛋白酶），在小肠继续（胰蛋白酶）。最终产物（氨基酸）在小肠吸收入毛细血管。

Fat:脂肪： Emulsified by bile (from liver/gallbladder) in the small intestine; then digested by pancreatic lipase. Final products (fatty acids + glycerol) absorbed into lacteals (lymphatic vessels) in the villi, then eventually reach the bloodstream.在小肠中由胆汁（来自肝脏/胆囊）乳化；再由胰脂肪酶消化。最终产物（脂肪酸 + 甘油）吸收入绒毛中的乳糜管（淋巴管），最终进入血液。

Where does the majority of nutrient absorption from digested food occur?消化食物中大多数营养物质的吸收在哪里发生？
§2 · Q1
The stomach胃
The large intestine大肠
The esophagus食道
The small intestine小肠
The small intestine is the primary site of both chemical digestion (pancreatic enzymes, bile) and absorption (through villi and microvilli into the bloodstream and lacteals). The large intestine mainly reabsorbs water; the stomach begins protein digestion but does not absorb nutrients significantly.小肠是化学消化（胰酶、胆汁）和吸收（通过绒毛和微绒毛进入血液和乳糜管）的主要场所。大肠主要重新吸收水分；胃开始蛋白质消化，但营养吸收不显著。
The small intestine, not the stomach or large intestine, is where most nutrients are absorbed. Its villi and microvilli create a massive surface area for absorption.小肠（而非胃或大肠）是大多数营养物质被吸收的地方。其绒毛和微绒毛形成巨大的吸收表面积。
Bile is produced by the liver and stored in the gallbladder. What is the primary role of bile in digestion?胆汁由肝脏产生，储存在胆囊中。胆汁在消化中的主要作用是什么？
§2 · Q2
Emulsifying (breaking up) fat droplets to increase the surface area for lipase action乳化（分解）脂肪滴，增大脂肪酶作用的表面积
Chemically digesting proteins into amino acids将蛋白质化学消化为氨基酸
Breaking down starch into sugars将淀粉分解为糖
Producing acid to denature food proteins产生酸以使食物蛋白质变性
Bile is not an enzyme; it is an emulsifier. It breaks large fat globules into smaller droplets, massively increasing the surface area for pancreatic lipase to act on. Protein digestion uses pepsin (stomach) and proteases (pancreas); starch digestion uses amylase; acid (HCl) is produced by the stomach, not the liver.胆汁不是酶；它是乳化剂。它将大脂肪球分解为更小的液滴，大幅增加胰脂肪酶的作用表面积。蛋白质消化使用胃蛋白酶（胃）和蛋白酶（胰腺）；淀粉消化使用淀粉酶；酸（盐酸）由胃产生，不是肝脏。
Bile emulsifies fat — it is not a digestive enzyme. It increases fat surface area so lipase can work more effectively.胆汁乳化脂肪——它不是消化酶。它增大脂肪表面积，使脂肪酶能更有效地发挥作用。
Going deeper — disorders of the digestive system (SBI3U E3.4; AB Biology 20 D GO1)深入 — 消化系统疾病（SBI3U E3.4；AB Biology 20 D GO1）

Common digestive disorders include: Ulcers: erosion of the stomach or duodenum lining, often caused by H. pylori bacteria or NSAID overuse, leading to pain and bleeding. Constipation: slow transit of feces through the large intestine; treatment involves increased fibre and water intake. Lactose intolerance: deficiency of lactase enzyme; lactose is not digested in the small intestine and instead fermented by gut bacteria in the large intestine, causing bloating and discomfort. Celiac disease: an autoimmune reaction to gluten that damages the villi of the small intestine, impairing nutrient absorption.常见消化系统疾病包括：溃疡：胃或十二指肠内壁侵蚀，通常由幽门螺旋杆菌或过量使用非甾体抗炎药引起，导致疼痛和出血。便秘：粪便在大肠中移动缓慢；治疗包括增加纤维和水分摄入。乳糖不耐受：乳糖酶缺乏；乳糖在小肠中不被消化，而是被大肠中的肠道细菌发酵，导致腹胀和不适。乳糜泻：对麸质的自身免疫反应，损害小肠绒毛，影响营养吸收。

Section 3 · The circulatory system第 3 节 · 循环系统

The Circulatory System循环系统

The heart, blood vessels, and blood (SBI3U E3.3; AB Biology 20 D GO2; BC A&P 12 Cardiovascular).心脏、血管与血液（SBI3U E3.3；AB Biology 20 D GO2；BC 解剖与生理 12 心血管）。
  • Heart structure:心脏结构： 4 chambers — right atrium, right ventricle, left atrium, left ventricle. Valves prevent backflow. The sinoatrial (SA) node is the heart's natural pacemaker.4 个腔室——右心房、右心室、左心房、左心室。瓣膜阻止血液倒流。窦房结（SA 结）是心脏的天然起搏器。
  • Two circulation circuits:两个循环回路： Pulmonary circulation (right heart → lungs → left heart): deoxygenated blood is oxygenated in the lungs. Systemic circulation (left heart → body → right heart): oxygenated blood is delivered to all body tissues.肺循环（右心 → 肺脏 → 左心）：去氧血在肺脏中氧合。体循环（左心 → 全身 → 右心）：含氧血输送至全身组织。
  • Blood vessels:血管： Arteries carry blood away from the heart (thick elastic walls). Veins carry blood toward the heart (thinner walls, valves). Capillaries link arteries to veins; site of gas/nutrient/waste exchange with tissues.动脉将血液从心脏输出（厚弹性壁）。静脉将血液输送回心脏（壁较薄，有瓣膜）。毛细血管连接动脉和静脉；是气体/营养/废物与组织交换的场所。
  • Blood components:血液成分： Red blood cells (erythrocytes) carry O₂ via haemoglobin. White blood cells (leukocytes) defend against infection. Platelets (thrombocytes) enable clotting. Plasma (liquid matrix) transports nutrients, hormones, and wastes.红细胞（红血球）通过血红蛋白携带 O₂。白细胞（白血球）抵御感染。血小板（凝血细胞）促进凝血。血浆（液态基质）运输营养、激素和废物。
T
Artery vs Vein vs Capillary: key differences动脉 vs 静脉 vs 毛细血管：关键区别
Feature特征Artery动脉Vein静脉Capillary毛细血管
Direction方向Away from heart离心Toward heart向心Connects arteries to veins连接动脉与静脉
Wall thickness壁厚Thick, elastic厚、有弹性Thinner, less elastic较薄、弹性差One cell thick仅一层细胞厚
Valves瓣膜No (except heart)无（心脏除外）Yes (prevent backflow)有（阻止倒流）No无
Function功能Transport blood under high pressure高压运输血液Return blood to heart将血液送回心脏Exchange O₂, CO₂, nutrients, waste交换 O₂、CO₂、营养和废物
Which chamber of the heart pumps oxygenated blood into the aorta and out to the systemic circulation?心脏哪个腔室将含氧血泵入主动脉并输送至体循环？
§3 · Q1
Right atrium右心房
Right ventricle右心室
Left ventricle左心室
Left atrium左心房
The left ventricle is the most muscular chamber; it pumps oxygenated blood (received from the left atrium, which came from the lungs) into the aorta for systemic distribution. The right ventricle pumps deoxygenated blood to the lungs via the pulmonary artery.左心室是最具肌肉力量的腔室；它将含氧血（从左心房接收，来自肺脏）泵入主动脉进行体循环分配。右心室通过肺动脉将去氧血泵送至肺脏。
The left ventricle pumps to the body (systemic). The right ventricle pumps to the lungs (pulmonary). The atria receive blood; the ventricles pump it out.左心室向全身泵血（体循环）。右心室向肺脏泵血（肺循环）。心房接收血液；心室将其泵出。
Capillaries are only one cell thick. Why is this important for their function?毛细血管仅一层细胞厚。这对其功能有何重要意义？
§3 · Q2
It allows rapid exchange of O₂, CO₂, nutrients, and waste by diffusion between blood and tissues使 O₂、CO₂、营养和废物能通过扩散在血液和组织间快速交换
It allows capillaries to withstand the high pressure of blood from the heart使毛细血管能承受来自心脏的高压血流
It allows capillaries to contract and propel blood forward使毛细血管能收缩推动血液前进
It helps capillaries filter bacteria from the blood帮助毛细血管从血液中过滤细菌
The ultra-thin single-cell wall of capillaries minimizes the diffusion distance between blood and tissue cells, enabling rapid exchange of O₂, CO₂, glucose, hormones, and metabolic wastes. This is why capillaries are the site of actual substance exchange — arteries and veins are too thick-walled for this.毛细血管超薄的单层细胞壁最小化了血液与组织细胞之间的扩散距离，使 O₂、CO₂、葡萄糖、激素和代谢废物能够快速交换。这就是毛细血管成为实际物质交换场所的原因——动脉和静脉壁太厚，无法完成这一功能。
Thin walls minimize diffusion distance for substance exchange. Thick walls (arteries) resist pressure; muscle (heart) pumps blood; filtering is done by lymph nodes and kidneys.薄壁最小化扩散距离以进行物质交换。厚壁（动脉）抵抗压力；肌肉（心脏）泵血；过滤由淋巴结和肾脏完成。
Going deeper — blood pressure, the cardiac cycle, and cardiovascular disease (SBI3U E3.3, E3.4; AB Biology 20 D GO2)深入 — 血压、心动周期与心血管疾病（SBI3U E3.3、E3.4；AB Biology 20 D GO2）

Blood pressure is expressed as systolic/diastolic (e.g. 120/80 mmHg): systolic is the pressure when the ventricles contract (systole); diastolic is the pressure when the ventricles relax (diastole). The SA node triggers electrical impulses that coordinate contraction. Coronary arteries supply the heart muscle itself with blood; blockage causes a myocardial infarction (heart attack). Atherosclerosis — buildup of fatty plaques in arterial walls — raises blood pressure and increases heart-attack and stroke risk. ABO and Rh blood groups (Alberta Biology 20 D GO2) determine blood-type compatibility for transfusions; the groups are defined by surface antigens on red blood cells and corresponding antibodies in plasma.血压用收缩压/舒张压表示（如 120/80 mmHg）：收缩压是心室收缩时的压力；舒张压是心室舒张时的压力。窦房结触发协调收缩的电冲动。冠状动脉为心肌本身供血；堵塞导致心肌梗死（心脏病发作）。动脉粥样硬化——动脉壁中脂肪斑块积聚——升高血压，增加心脏病发作和中风风险。ABO 和 Rh 血型（阿尔伯塔 Biology 20 D GO2）决定输血的血型相容性；血型由红细胞表面抗原及血浆中相应抗体定义。

Section 4 · The respiratory system第 4 节 · 呼吸系统

The Respiratory System呼吸系统

Gas exchange from atmosphere to cell (SBI3U E3.1; AB Biology 20 D GO1; BC A&P 12 Respiratory).从大气到细胞的气体交换（SBI3U E3.1；AB Biology 20 D GO1；BC 解剖与生理 12 呼吸系统）。
  • Pathway of air (inhalation):气流路径（吸气）： nasal passages (filter, warm, humidify) → pharynx → larynx (voice box; epiglottis prevents food from entering) → trachea (held open by C-shaped cartilage rings) → bronchi → bronchioles → alveoli.鼻腔（过滤、加温、湿润）→ 咽 → 喉（声箱；会厌阻止食物进入）→ 气管（C 形软骨环保持开放）→ 支气管 → 细支气管 → 肺泡。
  • Alveoli:肺泡： microscopic air sacs surrounded by capillaries. Features that maximize gas exchange: (1) enormous surface area (~70 m²); (2) very thin walls (one cell thick); (3) rich capillary supply; (4) moist surface. O₂ diffuses into the blood; CO₂ diffuses out.被毛细血管包围的微小气囊。最大化气体交换的特征：(1) 巨大表面积（约 70 平方米）；(2) 极薄壁（仅一层细胞厚）；(3) 丰富毛细血管；(4) 湿润表面。O₂ 扩散入血液；CO₂ 扩散出血液。
  • Ventilation mechanics:通气机制： Inhalation: diaphragm contracts (moves down) and intercostal muscles contract → thoracic cavity volume increases → pressure drops → air rushes in. Exhalation: diaphragm and intercostals relax → volume decreases → pressure rises → air expelled.吸气：膈肌收缩（向下移动），肋间肌收缩 → 胸腔体积增大 → 压力下降 → 空气涌入。呼气：膈肌和肋间肌放松 → 体积减小 → 压力上升 → 空气被排出。
Worked Example 2 · Gas exchange by diffusion例题 2 · 扩散进行气体交换

In the alveoli, the partial pressure of O₂ is higher in the air sac than in the surrounding capillary blood (which has just returned from the body tissues). Explain why O₂ moves from the alveolus into the blood, and which biological principle governs this movement.在肺泡中，气囊中 O₂ 的分压高于周围毛细血管血液中的分压（该血液刚从体组织返回）。解释 O₂ 为何从肺泡移入血液，以及哪种生物学原理控制这一运动。

Principle: diffusion (passive transport) down the concentration gradient.原理：顺浓度梯度的扩散（被动运输）。 O₂ moves from the region of higher partial pressure (alveolus) to lower partial pressure (capillary blood) by simple diffusion. No ATP is required. The thin alveolar wall and capillary wall (together just 2 cell layers) minimize diffusion distance, making this exchange extremely rapid. Simultaneously, CO₂ moves in the opposite direction (from blood, where it is produced by cellular respiration, into the alveolus, where its partial pressure is lower) and is exhaled.O₂ 通过简单扩散从分压较高处（肺泡）向分压较低处（毛细血管血液）移动。不需要 ATP。薄薄的肺泡壁和毛细血管壁（合计仅 2 层细胞）最小化扩散距离，使这种交换极为迅速。同时，CO₂ 向相反方向移动（从血液——细胞呼吸的产生地——进入肺泡，那里的分压较低）并被呼出。

What structural feature of alveoli most directly maximizes the rate of gas exchange with the blood?肺泡的哪种结构特征最直接地使与血液的气体交换速率最大化？
§4 · Q1
Their location deep inside the chest cavity它们位于胸腔深处
Their enormous number and thin walls, giving a large surface area and short diffusion distance其数量庞大和壁极薄，提供大的表面积和短的扩散距离
Their ability to contract and push gases into the blood其收缩并将气体推入血液的能力
Their thick muscular walls that prevent collapse其防止塌陷的厚肌肉壁
The ~300 million alveoli in the human lungs provide a total surface area of approximately 70 m². Their single-cell-thick walls and adjacent capillaries create a minimal diffusion distance (~0.2 μm), enabling O₂ and CO₂ to exchange almost instantaneously by diffusion.人肺中约 3 亿个肺泡提供约 70 平方米的总表面积。其单层细胞厚壁和相邻毛细血管形成极小的扩散距离（约 0.2 μm），使 O₂ 和 CO₂ 几乎可以瞬间通过扩散进行交换。
Surface area and diffusion distance are the key structural features. Alveoli do not contract; their thin (not thick) walls are what matters for diffusion.表面积和扩散距离是关键结构特征。肺泡不会收缩；其薄壁（而非厚壁）是扩散的关键。
During inhalation, which of the following correctly describes the mechanics?吸气时，下列哪项正确描述了力学机制？
§4 · Q2
The diaphragm relaxes, chest volume decreases, pressure rises, air enters膈肌松弛，胸腔体积减小，压力升高，气体进入
The diaphragm relaxes, chest volume increases, pressure drops, air enters膈肌松弛，胸腔体积增大，压力下降，气体进入
The diaphragm contracts, chest volume decreases, pressure drops, air enters膈肌收缩，胸腔体积减小，压力下降，气体进入
The diaphragm contracts, chest volume increases, pressure drops, air enters膈肌收缩，胸腔体积增大，压力下降，气体进入
Inhalation: diaphragm contracts and moves down, intercostal muscles contract and ribs move up and out → thoracic volume increases → lung pressure falls below atmospheric pressure → air flows in (Boyle's Law: pressure and volume are inversely related).吸气：膈肌收缩并向下移动，肋间肌收缩，肋骨向上和向外移动 → 胸腔体积增大 → 肺内压低于大气压 → 气体流入（波义耳定律：压力与体积成反比）。
Inhalation requires the diaphragm to contract (move down) to increase chest volume, which reduces pressure so air flows in. Relaxation of the diaphragm causes exhalation.吸气需要膈肌收缩（向下移动）以增大胸腔体积，从而降低压力使气体流入。膈肌松弛导致呼气。
Going deeper — respiratory disorders: asthma, emphysema, pneumonia (SBI3U E3.4; BC A&P 12)深入 — 呼吸系统疾病：哮喘、肺气肿、肺炎（SBI3U E3.4；BC 解剖与生理 12）

Asthma: inflammation and narrowing of the bronchioles, often triggered by allergens; reduces airflow and causes wheezing and breathlessness. Treated with bronchodilator inhalers. Emphysema: destruction of alveolar walls (usually from smoking), dramatically reducing surface area for gas exchange; irreversible. Pneumonia: infection (bacterial or viral) that fills the alveoli with fluid and pus, reducing the area available for gas exchange; treated with antibiotics if bacterial. The link to the circulatory system: any reduction in O₂ uptake at the lungs immediately reduces O₂ delivery to all body tissues by the cardiovascular system, illustrating the BC A&P 12 Big Idea of interdependence among organ systems.哮喘：细支气管炎症和收窄，通常由过敏原触发；减少气流，导致喘息和呼吸困难。用支气管扩张剂吸入器治疗。肺气肿：肺泡壁破坏（通常因吸烟），大幅减少气体交换表面积；不可逆转。肺炎：感染（细菌或病毒）使肺泡充满液体和脓液，减少可供气体交换的面积；细菌性肺炎可用抗生素治疗。与循环系统的联系：肺部 O₂ 摄取的任何减少都会立即减少心血管系统向全身组织的 O₂ 输送，说明了 BC 解剖与生理 12 大概念中器官系统间的相互依存。

Section 5 · The nervous system第 5 节 · 神经系统

The Nervous System神经系统

Rapid electrical control of the body (NGSS HS-LS1-2 stimulus-response; SBI4U E3.1; AB Biology 30 A GO1; BC A&P 12 Nervous).快速电信号控制身体（NGSS HS-LS1-2 刺激-反应；SBI4U E3.1；AB Biology 30 A GO1；BC 解剖与生理 12 神经）。
  • Organization:组织结构： Central nervous system (CNS) = brain + spinal cord. Peripheral nervous system (PNS) = all nerves outside the CNS. Afferent (sensory) neurons carry signals to the CNS; efferent (motor) neurons carry signals from the CNS to effectors (muscles, glands).中枢神经系统（CNS）= 大脑 + 脊髓。外周神经系统（PNS）= CNS 以外的所有神经。传入（感觉）神经元将信号传向 CNS；传出（运动）神经元将信号从 CNS 传向效应器（肌肉、腺体）。
  • The neuron:神经元： dendrites receive signals; cell body integrates; axon conducts signals to the next neuron or effector. Myelin sheath speeds conduction. A synapse is the junction where neurotransmitters carry the signal chemically across a gap.树突接收信号；细胞体整合信号；轴突将信号传向下一个神经元或效应器。髓鞘加快传导速度。突触是神经递质化学传递信号跨越间隙的连接点。
  • Reflex arc:反射弧： stimulus → receptor → afferent neuron → spinal cord (integration center) → efferent neuron → effector → response. Reflexes bypass the brain for speed.刺激 → 感受器 → 传入神经元 → 脊髓（整合中心）→ 传出神经元 → 效应器 → 反应。反射弧绕过大脑以提高速度。
What is the role of afferent (sensory) neurons in the nervous system?传入（感觉）神经元在神经系统中的作用是什么？
§5 · Q1
They carry signals from sense organs and receptors toward the CNS它们将来自感觉器官和感受器的信号传向中枢神经系统
They carry signals from the CNS to muscles and glands它们将信号从中枢神经系统传向肌肉和腺体
They connect the two hemispheres of the brain它们连接大脑的两个半球
They form the myelin sheath around motor neurons它们在运动神经元周围形成髓鞘
Afferent (sensory) neurons carry information from receptors toward the CNS for processing. Efferent (motor) neurons carry commands from the CNS to effectors. Interneurons connect them within the CNS.传入（感觉）神经元将来自感受器的信息传向中枢神经系统进行处理。传出（运动）神经元将指令从中枢神经系统传向效应器。中间神经元在中枢神经系统内连接它们。
Afferent = toward CNS (sensory). Efferent = away from CNS (motor). Direction: sensory receptor to brain or spinal cord.传入 = 传向 CNS（感觉）。传出 = 从 CNS 传出（运动）。方向：从感觉感受器传向大脑或脊髓。
In a simple reflex arc, where does integration of the incoming signal and sending of the motor response occur?在简单反射弧中，传入信号的整合和运动反应的发送在哪里发生？
§5 · Q2
The receptor感受器
The effector (muscle)效应器（肌肉）
The spinal cord脊髓
The cerebral cortex of the brain大脑皮层
In a simple reflex arc, the spinal cord integrates the afferent signal and sends the efferent response without involving the brain — which is what makes reflexes rapid.在简单反射弧中，脊髓整合传入信号并发送传出反应，整个过程不涉及大脑——这正是反射迅速的原因。
The spinal cord, not the brain, is the integration center for simple reflexes — this bypass is what makes the response faster.脊髓（而非大脑）是简单反射的整合中心——这种绕过使反应更快。
Going deeper — action potential and synaptic transmission (AB Biology 30 A GO1; SBI4U E3.1) Honors深入 — 动作电位与突触传递（AB Biology 30 A GO1；SBI4U E3.1）荣誉

A resting neuron maintains ~−70 mV via the Na⁺/K⁺ pump. When stimulus exceeds threshold, voltage-gated Na⁺ channels open: Na⁺ rushes in, depolarizing the membrane to ~+40 mV (action potential). Then K⁺ channels open, repolarizing the membrane. At the synapse, the action potential triggers vesicle release of neurotransmitters (e.g. acetylcholine, norepinephrine) into the synaptic cleft, binding receptors on the postsynaptic cell. Cholinesterase degrades acetylcholine to end the signal. Alberta Biology 30 A GO1 names acetylcholine, norepinephrine, and cholinesterase explicitly.静息神经元通过 Na⁺/K⁺ 泵维持约 −70 mV。当刺激超过阈值时，电压门控 Na⁺ 通道打开：Na⁺ 涌入，使膜去极化至约 +40 mV（动作电位）。然后 K⁺ 通道打开使膜复极化。在突触处，动作电位触发囊泡释放神经递质（如乙酰胆碱、去甲肾上腺素）进入突触间隙，与突触后细胞受体结合。胆碱酯酶降解乙酰胆碱以终止信号。阿尔伯塔 Biology 30 A GO1 明确命名了乙酰胆碱、去甲肾上腺素和胆碱酯酶。

Section 6 · The immune system第 6 节 · 免疫系统

The Immune System免疫系统

Three lines of defense (AB Biology 20 D GO2; BC A&P 12 Lymphatic/Immune; NGSS HS-LS1-3 homeostasis investigation).三道防线（AB Biology 20 D GO2；BC 解剖与生理 12 淋巴/免疫；NGSS HS-LS1-3 稳态调查）。
  • First line (non-specific, external barriers):第一道防线（非特异性，外部屏障）： skin (physical barrier; sweat and sebum are slightly acidic, inhibiting microbe growth), mucous membranes (trap pathogens), cilia in the respiratory tract (sweep pathogens out).皮肤（物理屏障；汗液和皮脂略呈酸性，抑制微生物生长）、黏膜（捕获病原体）、呼吸道纤毛（将病原体扫出）。
  • Second line (non-specific, internal defenses):第二道防线（非特异性，内部防御）： phagocytes (macrophages, neutrophils) engulf and destroy pathogens. Inflammation (redness, swelling, heat, pain) increases blood flow to the infected area. Fever raises body temperature to slow pathogen reproduction.吞噬细胞（巨噬细胞、中性粒细胞）吞噬和消灭病原体。炎症（发红、肿胀、发热、疼痛）增加感染区域的血流量。发烧升高体温以减缓病原体繁殖。
  • Third line (specific / adaptive immunity):第三道防线（特异性/适应性免疫）： B cells produce antibodies specific to an antigen; antibodies mark pathogens for destruction. T cells: helper T cells activate B cells and killer T cells; killer (cytotoxic) T cells destroy infected cells. Memory B and T cells provide long-term immunity after infection or vaccination.B 细胞产生针对特定抗原的抗体；抗体标记病原体以供消灭。T 细胞：辅助 T 细胞激活 B 细胞和杀伤 T 细胞；杀伤（细胞毒性）T 细胞消灭受感染细胞。记忆 B 细胞和 T 细胞在感染或接种疫苗后提供长期免疫。
A person who has previously recovered from chickenpox produces antibodies rapidly when exposed to the varicella-zoster virus again. Which immune system component is responsible for this rapid response?曾经康复的水痘患者再次接触水痘-带状疱疹病毒时，能迅速产生抗体。哪种免疫系统成分负责这种快速反应？
§6 · Q1
Macrophages (phagocytes)巨噬细胞（吞噬细胞）
Memory B cells and memory T cells记忆 B 细胞和记忆 T 细胞
The skin and mucous membranes皮肤和黏膜
Killer (cytotoxic) T cells杀伤（细胞毒性）T 细胞
After the first infection, the immune system produces memory B cells and memory T cells that persist for years. On re-exposure, these memory cells activate rapidly, producing a faster and stronger antibody response — this is the immunological basis of both natural immunity and vaccination.首次感染后，免疫系统产生持续数年的记忆 B 细胞和记忆 T 细胞。再次接触时，这些记忆细胞迅速激活，产生更快更强的抗体反应——这是自然免疫和疫苗接种的免疫学基础。
Memory B and T cells (from the specific/adaptive immune system) provide the rapid secondary response. Macrophages and skin are non-specific; killer T cells destroy infected cells rather than producing antibodies.记忆 B 和 T 细胞（来自特异性/适应性免疫系统）提供快速的二次反应。巨噬细胞和皮肤是非特异性的；杀伤 T 细胞消灭受感染细胞而非产生抗体。
Which component of the immune system is categorized as part of the first line of defense?免疫系统中哪种成分属于第一道防线？
§6 · Q2
B cells producing antibodies产生抗体的 B 细胞
Macrophages engulfing bacteria吞噬细菌的巨噬细胞
Killer T cells destroying infected cells消灭受感染细胞的杀伤 T 细胞
Skin acting as a physical barrier against pathogens皮肤作为抵御病原体的物理屏障
The first line of defense consists of non-specific external barriers: skin, mucous membranes, and cilia. These prevent pathogens from entering the body. B cells and killer T cells are the third line (specific immunity); macrophages are the second line (non-specific internal).第一道防线由非特异性外部屏障组成：皮肤、黏膜和纤毛。这些阻止病原体进入身体。B 细胞和杀伤 T 细胞是第三道防线（特异性免疫）；巨噬细胞是第二道防线（非特异性内部）。
Skin is the first line (external barrier). Macrophages = second line (non-specific internal). B and T cells = third line (specific/adaptive). The order matters on exams.皮肤是第一道防线（外部屏障）。巨噬细胞 = 第二道防线（非特异性内部）。B 和 T 细胞 = 第三道防线（特异性/适应性）。顺序在考试中很重要。
Going deeper — ABO blood groups, vaccines, and autoimmune disease (AB Biology 20 D GO2; BC A&P 12)深入 — ABO 血型、疫苗与自身免疫性疾病（AB Biology 20 D GO2；BC 解剖与生理 12）

ABO blood groups (Alberta Biology 20 D GO2): blood type is determined by antigens on red blood cell surfaces and antibodies in plasma. Type A has A antigens and anti-B antibodies; Type B has B antigens and anti-A; Type AB has both antigens and no antibodies (universal recipient); Type O has no antigens and both antibodies (universal donor). Vaccines work by introducing a weakened/killed pathogen or its antigen, triggering the adaptive immune response and creating memory cells without causing disease. Autoimmune diseases (e.g. Type 1 diabetes, rheumatoid arthritis, lupus) occur when the immune system fails to distinguish self from non-self and attacks the body's own tissues — an example of homeostatic failure at the system level.ABO 血型（阿尔伯塔 Biology 20 D GO2）：血型由红细胞表面抗原和血浆中的抗体决定。A 型有 A 抗原和抗 B 抗体；B 型有 B 抗原和抗 A 抗体；AB 型有两种抗原但无抗体（万能受血者）；O 型无抗原但有两种抗体（万能供血者）。疫苗通过引入减弱/灭活的病原体或其抗原起作用，触发适应性免疫反应并产生记忆细胞，而不引起疾病。自身免疫性疾病（如 1 型糖尿病、类风湿关节炎、狼疮）发生在免疫系统无法区分自身与非自身并攻击身体自身组织时——这是系统层面稳态失败的例子。

Section 7 · Endocrine and reproductive systems第 7 节 · 内分泌系统与生殖系统

The Endocrine and Reproductive Systems: Overview内分泌系统与生殖系统：概述

Chemical signaling and continuation of the species (SBI4U E3.1, E3.2; AB Biology 30 A GO2 + B; BC A&P 12 Endocrine + Reproductive).化学信号传导与种族延续（SBI4U E3.1、E3.2；AB Biology 30 A GO2 + B；BC 解剖与生理 12 内分泌 + 生殖）。
  • Endocrine system:内分泌系统： glands secrete hormones (chemical messengers) directly into the bloodstream. Hormones travel to target cells/organs and cause a response. Slower than the nervous system (minutes to hours vs milliseconds) but longer-lasting.腺体将激素（化学信使）直接分泌入血液。激素随血液流向靶细胞/靶器官并引起反应。比神经系统慢（分钟至小时 vs 毫秒），但持续时间更长。
  • Key glands and hormones:主要腺体与激素： Pituitary (master gland; secretes TSH, FSH, LH, GH, ADH). Thyroid (thyroxine: regulates metabolic rate). Pancreas (insulin: lowers blood glucose; glucagon: raises blood glucose). Adrenal glands (adrenaline: fight-or-flight; cortisol: stress). Gonads (estrogen, progesterone, testosterone).垂体（主腺；分泌 TSH、FSH、LH、GH、ADH）。甲状腺（甲状腺素：调节代谢率）。胰腺（胰岛素：降低血糖；胰高血糖素：升高血糖）。肾上腺（肾上腺素：应激反应；皮质醇：压力反应）。性腺（雌激素、孕激素、睾酮）。
  • Negative feedback (homeostasis):负反馈（稳态）： when blood glucose rises (after eating), the pancreas releases insulin, driving glucose into cells. As glucose levels fall back to normal, insulin release decreases. This closed-loop control is the mechanism for maintaining homeostasis (NGSS HS-LS1-3).餐后血糖升高时，胰腺释放胰岛素，将葡萄糖驱入细胞。随着血糖水平恢复正常，胰岛素释放减少。这种闭环控制是维持稳态的机制（NGSS HS-LS1-3）。
  • Reproductive system overview:生殖系统概述： Female: ovaries (egg production + estrogen/progesterone), Fallopian tubes (transport of egg to uterus), uterus (site of embryo development). Male: testes (sperm production + testosterone), vas deferens (transport), prostate + seminal vesicles (fluids). Fertilization typically occurs in the Fallopian tube.女性：卵巢（产生卵子 + 雌激素/孕激素）、输卵管（将卵子运至子宫）、子宫（胚胎发育场所）。男性：睾丸（产生精子 + 睾酮）、输精管（运输）、前列腺 + 精囊（提供精液成分）。受精通常发生在输卵管。
After a high-carbohydrate meal, blood glucose levels rise. Which hormone is released, and what is its effect?高碳水化合物餐后，血糖水平升高。哪种激素被释放，其效果是什么？
§7 · Q1
Glucagon is released; it raises blood glucose further胰高血糖素被释放；它进一步升高血糖
Adrenaline is released; it converts glycogen to glucose肾上腺素被释放；它将糖原转化为葡萄糖
Thyroxine is released; it speeds up metabolism甲状腺素被释放；它加速代谢
Insulin is released; it stimulates cells to absorb glucose, lowering blood glucose胰岛素被释放；它刺激细胞吸收葡萄糖，降低血糖
Rising blood glucose triggers beta cells of the pancreas to release insulin. Insulin signals body cells (especially liver, muscle, and fat cells) to take up glucose and either use it for energy or store it as glycogen/fat. This is a classic negative feedback loop: the response (glucose uptake) opposes the change (high glucose) to restore homeostasis.血糖升高触发胰腺 β 细胞释放胰岛素。胰岛素信号通知体细胞（尤其是肝脏、肌肉和脂肪细胞）摄取葡萄糖，用于产能或以糖原/脂肪形式储存。这是经典的负反馈回路：反应（葡萄糖摄取）对抗变化（高血糖）以恢复稳态。
Insulin (not glucagon, adrenaline, or thyroxine) responds to high blood glucose by stimulating cellular uptake. Glucagon has the opposite effect (releases glucose when blood glucose is low).胰岛素（而非胰高血糖素、肾上腺素或甲状腺素）通过刺激细胞摄取来响应高血糖。胰高血糖素有相反的效果（血糖低时释放葡萄糖）。
How does the endocrine system differ from the nervous system in its control of body functions?内分泌系统与神经系统在控制身体功能方面有何不同？
§7 · Q2
The endocrine system uses electrical signals; the nervous system uses chemical signals内分泌系统使用电信号；神经系统使用化学信号
The endocrine system uses hormones in the blood for slower, longer-lasting effects; the nervous system uses electrical impulses for rapid, brief responses内分泌系统通过血液中的激素产生较慢但持久的效果；神经系统通过电冲动产生快速、短暂的反应
The endocrine system acts only on muscles; the nervous system acts only on glands内分泌系统仅作用于肌肉；神经系统仅作用于腺体
The two systems are completely independent and never interact两个系统完全独立，从不相互作用
The nervous system transmits electrical impulses at very high speed (milliseconds; localized, precise). The endocrine system releases hormones into the blood (minutes to hours; widespread, longer-lasting effects). The two systems cooperate — for example, the hypothalamus in the brain controls the pituitary gland, linking neural control to hormonal control.神经系统以极高速度（毫秒；局部、精确）传递电冲动。内分泌系统将激素释放入血液（分钟至小时；广泛、持久的效果）。两个系统相互协作——例如，大脑中的下丘脑控制垂体，将神经控制与激素控制联系起来。
The endocrine system uses chemical hormones (slow, long-lasting, widespread); the nervous system uses electrical impulses (fast, brief, targeted). They interact — the hypothalamus-pituitary axis is the key link.内分泌系统使用化学激素（慢、持久、广泛）；神经系统使用电冲动（快、短暂、有针对性）。它们相互作用——下丘脑-垂体轴是关键连接。
Going deeper — the menstrual cycle, reproductive hormones, and diabetes mellitus (AB Biology 30 B GO2; SBI4U E3.2) Honors深入 — 月经周期、生殖激素与糖尿病（AB Biology 30 B GO2；SBI4U E3.2）荣誉

The menstrual cycle is controlled by four hormones: FSH (stimulates follicle development), LH (triggers ovulation at the cycle's midpoint), estrogen (builds up the uterine lining, feeds back to trigger LH surge), and progesterone (maintains the uterine lining after ovulation; falls if no fertilization, causing menstruation). Testosterone in males is produced by the testes under stimulation from LH; FSH stimulates sperm production. Diabetes mellitus Type 1: the immune system destroys beta cells of the pancreas, so no insulin is produced — blood glucose remains dangerously high. Type 2: body cells become insulin-resistant. Both illustrate how endocrine failure disrupts homeostasis across multiple organ systems (BC A&P 12: "Disease as an imbalance in homeostasis").月经周期由四种激素控制：FSH（刺激卵泡发育）、LH（在周期中点触发排卵）、雌激素（构建子宫内膜，通过反馈触发 LH 峰值）和孕激素（排卵后维持子宫内膜；若无受精则下降，引起月经）。男性的睾酮由睾丸在 LH 刺激下产生；FSH 刺激精子生成。1 型糖尿病：免疫系统破坏胰腺 β 细胞，导致不产生胰岛素——血糖持续危险升高。2 型糖尿病：体细胞产生胰岛素抵抗。两者都说明内分泌系统失败如何破坏多个器官系统的稳态（BC 解剖与生理 12："疾病是稳态的失衡"）。

Exam Tactics考试策略

Exam Strategy and Common Pitfalls考试策略与常见陷阱

System-tracing questions系统追踪题
  • Trace the pathway, name the structures, state the process at each stop.追踪路径，命名结构，说明每个环节的过程。 Example: "oxygen enters the alveoli by inhalation, diffuses across the alveolar and capillary walls into the blood, binds haemoglobin in red blood cells, and is transported by the circulatory system to tissues where it diffuses into cells for aerobic respiration."示例："氧气通过吸气进入肺泡，扩散穿过肺泡壁和毛细血管壁进入血液，与红细胞中的血红蛋白结合，由循环系统运输至组织，在那里扩散入细胞进行有氧呼吸。"
  • Link systems explicitly.明确联系各系统。 The circulatory system is the connector: it delivers O₂ (from respiratory), glucose (from digestive), and hormones (from endocrine) to every other system, while removing CO₂ and waste. NGSS HS-LS1-2 expects this interacting-systems model.循环系统是连接者：它将 O₂（来自呼吸系统）、葡萄糖（来自消化系统）和激素（来自内分泌系统）输送至每个系统，同时带走 CO₂ 和废物。NGSS HS-LS1-2 期望这种相互作用的系统模型。
Anatomy identification questions解剖辨认题
  • Always pair structure with function.始终将结构与功能配对。 Naming "alveoli" alone rarely wins full marks; "alveoli — microscopic air sacs in the lungs where O₂ and CO₂ are exchanged by diffusion with the blood" is the complete answer.仅写"肺泡"很少能得满分；"肺泡——肺中的微小气囊，O₂ 和 CO₂ 通过扩散与血液在此交换"才是完整答案。
  • Feedback vs feedforward.负反馈 vs 前馈。 Most homeostatic mechanisms are negative feedback (the response opposes the change). Do not confuse with positive feedback (response amplifies the change; e.g. oxytocin in childbirth, blood clotting). NGSS HS-LS1-3 focuses on negative feedback investigations.大多数稳态机制是负反馈（反应对抗变化）。不要与正反馈混淆（反应放大变化；如分娩中的催产素、血液凝固）。NGSS HS-LS1-3 侧重于负反馈调查。
Disease and disorder questions疾病与紊乱题
  • Link the disorder to the disrupted structure or function.将疾病与被破坏的结构或功能联系起来。 Atherosclerosis → arterial narrowing → reduced blood flow → increased heart attack risk. Asthma → bronchiole narrowing → reduced airflow. Type 1 diabetes → beta cell destruction → no insulin → hyperglycemia. Pattern: cause → structural change → functional consequence.动脉粥样硬化 → 动脉变窄 → 血流减少 → 心脏病发作风险增加。哮喘 → 细支气管变窄 → 气流减少。1 型糖尿病 → β 细胞破坏 → 无胰岛素 → 高血糖。规律：原因 → 结构改变 → 功能后果。
Active Recall主动复习

Flashcards闪卡

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Four animal tissue types?四种动物组织类型？
Epithelial (covering/lining), Connective (support/binding), Muscle (contraction), Nervous (signaling).上皮组织（覆盖/内衬）、结缔组织（支撑/连接）、肌肉组织（收缩）、神经组织（信号传导）。
Path of food through the digestive system?食物通过消化系统的路径？
Mouth → Esophagus → Stomach → Small intestine (most absorption) → Large intestine (water) → Rectum → Anus.口腔 → 食道 → 胃 → 小肠（主要吸收）→ 大肠（水分）→ 直肠 → 肛门。
Role of bile in digestion?胆汁在消化中的作用？
Emulsifies (breaks up) fat droplets, increasing surface area for lipase action. Produced by liver, stored in gallbladder.乳化（分解）脂肪液滴，增大脂肪酶的作用表面积。由肝脏产生，储存在胆囊。
Two circulatory circuits?两个循环回路？
Pulmonary: right heart → lungs → left heart (oxygenates blood). Systemic: left heart → body → right heart (delivers O2 to tissues).肺循环：右心 → 肺脏 → 左心（氧合血液）。体循环：左心 → 全身 → 右心（向组织输送 O2）。
Artery vs vein — key differences?动脉 vs 静脉 — 关键区别？
Arteries: carry blood away from heart, thick elastic walls, no valves. Veins: carry blood toward heart, thinner walls, valves prevent backflow.动脉：血液离心，壁厚有弹性，无瓣膜。静脉：血液向心，壁较薄，瓣膜阻止倒流。
Why are alveoli efficient for gas exchange?肺泡为何高效进行气体交换？
Enormous number (~300 million), one-cell-thick walls, rich capillary supply → large surface area + minimal diffusion distance.数量庞大（约 3 亿），壁仅一层细胞厚，毛细血管丰富 → 大表面积 + 最小扩散距离。
Inhalation mechanics?吸气机制？
Diaphragm contracts (moves down) + intercostals contract → chest volume increases → pressure drops → air flows in.膈肌收缩（向下移动）+ 肋间肌收缩 → 胸腔体积增大 → 压力下降 → 气体流入。
CNS vs PNS?中枢神经系统 vs 外周神经系统？
CNS = brain + spinal cord (integration). PNS = all other nerves. Afferent (sensory) carry signals to CNS; efferent (motor) carry signals from CNS to effectors.CNS = 大脑 + 脊髓（整合）。PNS = 所有其他神经。传入（感觉）将信号传向 CNS；传出（运动）将信号从 CNS 传向效应器。
Three lines of immune defense?三道免疫防线？
1st: skin/mucous membranes (barriers). 2nd: phagocytes + inflammation (non-specific internal). 3rd: B cells (antibodies) + T cells (specific/adaptive).第一道：皮肤/黏膜（屏障）。第二道：吞噬细胞 + 炎症（非特异性内部）。第三道：B 细胞（抗体）+ T 细胞（特异性/适应性）。
Role of memory B and T cells?记忆 B 细胞和 T 细胞的作用？
Persist after infection; respond rapidly and strongly upon re-exposure to the same antigen — the basis of immunological memory and vaccination.感染后持续存在；再次接触相同抗原时迅速强烈响应——免疫记忆和疫苗接种的基础。
Insulin vs glucagon — when is each released?胰岛素 vs 胰高血糖素 — 各何时释放？
Insulin: released when blood glucose is HIGH → stimulates cells to absorb glucose (lowers blood glucose). Glucagon: released when blood glucose is LOW → stimulates liver to release glucose (raises blood glucose).胰岛素：血糖高时释放 → 刺激细胞吸收葡萄糖（降低血糖）。胰高血糖素：血糖低时释放 → 刺激肝脏释放葡萄糖（升高血糖）。
Endocrine vs nervous system speed?内分泌系统 vs 神经系统速度？
Nervous: milliseconds (electrical impulses; localized, precise). Endocrine: minutes to hours (hormones in blood; widespread, longer-lasting).神经系统：毫秒（电冲动；局部、精确）。内分泌系统：分钟至小时（血液中的激素；广泛、持久）。
What is a negative feedback loop?什么是负反馈回路？
A control mechanism where the response opposes the original change, restoring a set point. Example: body temperature — if too hot, sweating cools the body back to normal.一种控制机制，其中反应对抗原始变化，恢复设定点。示例：体温——太热时，出汗使身体冷却恢复正常。
NGSS HS-LS1-2 core expectation for human anatomy?NGSS HS-LS1-2 对人体解剖的核心期望？
"Develop and use a model to illustrate the hierarchical organization of interacting systems that provide specific functions within multicellular organisms." Focus: systems-model, not molecular detail."建立并使用模型，说明多细胞生物体内为特定功能服务的相互作用系统的层级组织。"重点：系统模型，而非分子细节。
Mixed Practice综合练习

Practice Quiz综合测验

Oxygen is absorbed from the alveoli into the blood by diffusion. What single structural feature of alveoli most directly enables this rapid diffusion?氧气通过扩散从肺泡被吸收入血液。肺泡的哪个单一结构特征最直接地使这种快速扩散成为可能？
Q1
Their location inside the rib cage它们位于胸腔内
Their one-cell-thick walls minimizing diffusion distance其仅一层细胞厚的壁最小化扩散距离
Their ability to contract and push oxygen into blood其收缩并将氧气推入血液的能力
Their thick muscular walls that prevent collapse其防止塌陷的厚肌肉壁
The one-cell-thick wall of each alveolus (and the adjacent capillary wall) creates a diffusion distance of only ~0.2 μm, allowing O₂ and CO₂ to exchange almost instantaneously. Their enormous number also maximizes total surface area (~70 m²).每个肺泡（及相邻毛细血管壁）仅一层细胞厚的壁形成约 0.2 μm 的扩散距离，使 O₂ 和 CO₂ 几乎瞬间完成交换。其庞大数量也使总表面积最大化（约 70 平方米）。
Thin walls (minimizing diffusion distance) are the key structural feature for gas exchange. Alveoli do not contract; thick walls would slow diffusion, not speed it.薄壁（最小化扩散距离）是气体交换的关键结构特征。肺泡不会收缩；厚壁会减慢扩散，而非加快。
Which chamber of the heart pumps deoxygenated blood to the lungs?心脏哪个腔室将去氧血泵送至肺脏？
Q2
Left atrium左心房
Left ventricle左心室
Right ventricle右心室
Right atrium右心房
The right ventricle receives deoxygenated blood from the right atrium (which collected it from the body via the venae cavae) and pumps it to the lungs via the pulmonary artery. The left ventricle pumps oxygenated blood to the body.右心室从右心房（通过腔静脉从体内收集的血液）接收去氧血，并通过肺动脉将其泵送至肺脏。左心室将含氧血泵送至全身。
Right ventricle → lungs (pulmonary circulation). Left ventricle → body (systemic circulation). Atria receive blood; ventricles pump it out.右心室 → 肺脏（肺循环）。左心室 → 全身（体循环）。心房接收血液；心室将其泵出。
A person is diagnosed with Type 1 diabetes mellitus. Their immune system has destroyed the beta cells of the pancreas. What is the direct consequence?一人被诊断为 1 型糖尿病。其免疫系统已破坏胰腺的 β 细胞。直接后果是什么？
Q3
No insulin is produced; blood glucose cannot be lowered after meals不产生胰岛素；餐后血糖无法降低
No glucagon is produced; blood glucose stays permanently elevated不产生胰高血糖素；血糖永久升高
Bile is no longer produced; fats cannot be digested不再产生胆汁；脂肪无法消化
The nervous system can no longer regulate heart rate神经系统无法再调节心率
Beta cells of the pancreas produce insulin. Without them, no insulin is secreted, so blood glucose rises and stays high (hyperglycemia) after meals. Glucagon is produced by alpha cells (also in the pancreas); bile comes from the liver; heart rate is regulated by the SA node and autonomic nervous system — none of these are affected.胰腺的 β 细胞产生胰岛素。没有它们，胰岛素不分泌，因此餐后血糖升高并持续偏高（高血糖症）。胰高血糖素由 α 细胞（也在胰腺中）产生；胆汁来自肝脏；心率由窦房结和自主神经系统调节——这些均不受影响。
Beta cells make insulin (not glucagon, not bile). Without insulin, blood glucose cannot be brought down after eating — this is the core problem in Type 1 diabetes.β 细胞产生胰岛素（不是胰高血糖素，不是胆汁）。没有胰岛素，餐后血糖无法降低——这是 1 型糖尿病的核心问题。
A student says the first line of immune defense is antibody production. Correct this statement.一名学生说免疫的第一道防线是产生抗体。请纠正这一说法。
Q4
The statement is correct; B cells produce antibodies immediately说法正确；B 细胞立即产生抗体
The first line is macrophages engulfing pathogens第一道防线是巨噬细胞吞噬病原体
The first line is fever and inflammation第一道防线是发烧和炎症
Antibody production is the third line; the first line is physical/chemical barriers like skin and mucous membranes抗体产生是第三道防线；第一道防线是皮肤和黏膜等物理/化学屏障
First line = skin, mucous membranes, cilia (non-specific external barriers). Second line = phagocytes, inflammation, fever (non-specific internal). Third line = B cells (antibodies) and T cells (specific/adaptive immunity). The student confused the first and third lines.第一道防线 = 皮肤、黏膜、纤毛（非特异性外部屏障）。第二道防线 = 吞噬细胞、炎症、发烧（非特异性内部）。第三道防线 = B 细胞（抗体）和 T 细胞（特异性/适应性免疫）。该学生混淆了第一和第三道防线。
Antibodies (B cells) = third line. The first line is the physical barriers (skin, mucous membranes) that prevent pathogens from entering. The order: barriers → non-specific internal → specific adaptive.抗体（B 细胞）= 第三道防线。第一道防线是阻止病原体进入的物理屏障（皮肤、黏膜）。顺序：屏障 → 非特异性内部 → 特异性适应性。
The NGSS HS-LS1-2 Assessment Boundary states that assessment "does not include interactions and functions at the molecular or chemical reaction level." Which approach is therefore most appropriate for an NGSS exam?NGSS HS-LS1-2 评估边界规定评估"不包括分子或化学反应层面的互动与功能"。因此哪种方法最适合 NGSS 考试？
Q5
Memorize the names of all enzymes in the digestive system记忆消化系统所有酶的名称
Use a systems-model to explain how the circulatory system delivers oxygen from lungs to muscles, naming the organs involved使用系统模型解释循环系统如何将氧气从肺脏输送至肌肉，并说明涉及的器官
Describe the action potential mechanism at the ionic level在离子水平描述动作电位机制
Calculate hormone concentrations using feedback equations用反馈方程计算激素浓度
NGSS HS-LS1-2 expects the systems-model approach: trace function at the organ and system level (circulatory delivers O₂ from lungs to tissues). Molecular details (enzyme names, ion channels, hormone equations) are excluded by the Assessment Boundary. The Clarification Statement gives "nutrient uptake, water delivery, and organism movement in response to neural stimuli" as the expected level of detail.NGSS HS-LS1-2 期望系统模型方法：在器官和系统层面追踪功能（循环系统将 O₂ 从肺脏输送至组织）。分子细节（酶名称、离子通道、激素方程）被评估边界排除。说明声明将"营养摄取、水分输送和生物体对神经刺激的运动响应"作为期望的细节水平。
NGSS expects the systems-model level: organs interacting within systems. Enzyme names, ion channels, and calculations are provincial (ON/BC/AB) or molecular-biology content, not NGSS HS-LS1-2 content.NGSS 期望系统模型层面：器官在系统内相互作用。酶名称、离子通道和计算属于省级（ON/BC/AB）或分子生物学内容，不是 NGSS HS-LS1-2 内容。
Self-check自查

Readiness Checklist准备就绪清单

Tick each item when you can do it cold, without notes, on a first attempt.能在无笔记、首次尝试下完成，再勾选每一项。

0 / 11 mastered已掌握 0 / 11
Next Steps后续衔接

What This Feeds Into本单元的去向

Human Anatomy and Physiology is the culminating systems unit of High School Biology. The organ systems covered here build directly on the cellular and molecular foundations from earlier units and simultaneously open pathways to higher-level courses.人体解剖与生理学是高中生物学的最终系统单元。本指南涵盖的器官系统直接建立在早期单元的细胞和分子基础之上，同时开辟了通向高级课程的路径。

Within High School Biology.在 HS Biology 内部。

Cell Structure and Function (Unit 1) provides the cell specialization knowledge that explains why neurons, red blood cells, and epithelial cells look different. Biochemistry (Unit 2) explains the enzyme systems in the digestive tract. Cellular Energetics (Unit 3) explains why heart and skeletal muscle cells are packed with mitochondria. Molecular Genetics (Unit 6) explains how the endocrine system's protein hormones are synthesized. Homeostasis (Unit 11) extends the negative feedback principles introduced in this guide into a full systems treatment. Evolution (Unit 7) explains why the human body plan evolved as it did.细胞结构与功能（第 1 单元）提供的细胞特化知识解释了神经元、红细胞和上皮细胞为何形态各异。生物化学（第 2 单元）解释了消化道中的酶系统。细胞能量学（第 3 单元）解释了为何心肌细胞和骨骼肌细胞充满线粒体。分子遗传学（第 6 单元）解释了内分泌系统的蛋白质激素如何合成。稳态（第 11 单元）将本指南中引入的负反馈原则扩展为完整的系统处理。进化（第 7 单元）解释了人体结构为何如此演化。

Feeds into AP Biology and IB Biology.衔接 AP Biology 与 IB Biology。

AP Biology Unit 9 (Cellular Signaling) and Unit 5 (Heredity) connect directly to the endocrine and immune content here. IB Biology HL Topic D (Medicine and Drugs) and Topic E (Ecology and Evolution) draw on the organ-system and homeostasis framing. BC Anatomy and Physiology 12 is itself a course that mirrors this guide at greater depth — use this guide as the conceptual foundation before tackling that course's detail.AP Biology 第 9 单元（细胞信号传导）和第 5 单元（遗传）直接与此处的内分泌和免疫内容相关。IB Biology HL D 主题（医学与药物）和 E 主题（生态与进化）借鉴了器官系统和稳态框架。BC 解剖与生理 12 本身就是一门以更大深度呈现本指南内容的课程——在处理该课程的细节之前，使用本指南作为概念基础。

DINGRUI SCHOLARS

High School Biology · Human Anatomy and Physiology · v1高中生物 · 人体解剖与生理学 · v1