📚 Case Study Practice in Year 7 Biology | 生物案例分析实战演练
In Year 7 SQA Biology, case study questions are designed to test how well you can apply scientific knowledge to real-world situations. Instead of simply recalling facts, you need to interpret data, draw conclusions and explain biological ideas clearly. This article will guide you through the key skills and example scenarios so you can tackle these questions with confidence.
在七年级 SQA 生物中，案例研究题旨在测试你将科学知识应用于实际情境的能力。你不只是回忆事实，还需要解释数据、得出结论并清晰地说明生物学观点。本文将带你掌握关键技能并演练样例情境，让你自信应对这类题目。
1. Understanding Case Study Questions | 理解案例分析题
A case study question provides a scenario, often with a short story, table or graph. It may ask you to describe, explain, predict or evaluate. The first step is to read the question carefully and identify the command word (e.g. 'explain' means you must give reasons, not just state facts).
案例分析题会给出一个情境，通常带有一段小故事、表格或图表。它可能要求你描述、解释、预测或评价。第一步是仔细读题，识别指令词（例如，"解释"意味着你必须给出原因，而不仅仅是陈述事实）。
Next, look for clues in the text and data. Underline numbers, units and scientific terms. Think about which topic the scenario relates to – cells, food chains, human body systems or plant growth.
接着，在文字和数据中寻找线索。圈出数字、单位和科学术语。想想这个情境涉及哪个主题——细胞、食物链、人体系统还是植物生长。
Always answer in full sentences and refer back to the data provided. Avoid vague statements like 'it increased'; instead say 'the heart rate increased from 72 to 110 bpm after exercise'.
始终用完整句子作答，并回扣所给数据。避免使用像"它上升了"这样的模糊说法；而应该说"运动后心率从 72 bpm 上升到 110 bpm"。
A good case study answer therefore has three layers: a clear statement, the data that supports it, and the biological reason behind it.
因此，一份优秀的案例分析答案包含三个层次：清晰的陈述、支持它的数据，以及背后的生物学原理。
2. Command Words and What They Demand | 指令词及其作答要求
Command words tell you exactly how much detail the marker expects and which skill is being tested. Highlighting the command word before you start writing saves marks that are otherwise lost through misunderstanding.
指令词明确告诉你要写多少细节，以及这道题在考查哪项技能。动笔前先标出指令词，能避免因理解偏差而白白丢分。
| Command word | 指令词 | What it requires | 作答要求 |
| State / Name | A short fact, no reason needed. 简短事实，无需原因。 |
| Describe | Say what happens or what you see. 说明发生了什么或你观察到什么。 |
| Explain | Give a reason using 'because'. 用"因为"给出原因。 |
| Predict | Say what will happen next and why. 说出接下来会发生什么及原因。 |
| Evaluate | Weigh up strengths and weaknesses, then judge. 权衡优缺点后作出判断。 |
Notice that 'describe' and 'explain' are not interchangeable. A description of a graph reads the pattern; an explanation links that pattern to a biological process such as respiration, photosynthesis or enzyme activity.
注意，"描述"和"解释"不能互换。对图表的描述是读出趋势；解释则要把这一趋势与呼吸作用、光合作用或酶活性等生物学过程联系起来。
3. Setting the Scene: Scenarios, Tables and Graphs | 情境、表格与图表
Most case studies begin with a short context paragraph. It might describe a pupil testing their pulse, a farmer changing a crop, or a pond being polluted. This context is not decoration – it often contains the variables you need.
大多数案例研究都以一段简短的情境开头。它可能描述一名学生测量脉搏、一位农民更换作物，或者池塘被污染。这段情境不是装饰——它往往包含了你需要的变量。
Tables give you controlled conditions and results side by side. Graphs show trends over time or across groups. Read the axis labels and units before you read the numbers, and check whether the graph starts at zero.
表格把控制条件和结果并排呈现。图表展示随时间或跨组别的趋势。先读坐标轴标签和单位，再看数字，并检查图表是否从零点开始。
If several groups are compared, identify the independent variable (what was changed), the dependent variable (what was measured) and at least one control variable (what was kept the same).
如果比较了多个组别，要找出自变量（被改变的因素）、因变量（被测量的因素）以及至少一个控制变量（保持相同的因素）。
4. Finding Clues in Text and Data | 在文字与数据中寻找线索
Active reading is the single most useful habit in case study work. Train yourself to mark the page as you go rather than reading passively from top to bottom.
主动阅读是案例分析中最有用的习惯。要训练自己边读边做标记，而不是被动地从头读到尾。
- Underline every number together with its unit – 60 bpm, 25 °C, 12 cm³. 把每个数字连同单位一起划出来——60 bpm、25 °C、12 cm³。
- Circle scientific terms such as 'diffusion', 'glucose', 'predator' or 'transpiration'. 圈出"扩散""葡萄糖""捕食者""蒸腾作用"等科学术语。
- Box comparison words: increase, decrease, higher, lower, faster, twice. 把比较词框起来：上升、下降、更高、更低、更快、两倍。
- Note anomalies – a result that does not fit the pattern is usually worth a mark. 标记异常值——不符合规律的结果通常值得一分。
Once you have marked the data, write a one-line summary in the margin. If you cannot summarise it in one line, you have not yet understood the scenario well enough to answer.
标记完数据后，在页边写一句总结。如果你无法用一句话概括，说明你对情境的理解还不足以作答。
5. Identifying the Biology Topic | 判断涉及的生物学主题
Every scenario is built on a topic from the course. Naming that topic quickly lets you recall the correct vocabulary and the correct mechanism.
每个情境都建立在课程中的某个主题之上。快速说出该主题，能让你回想起正确的词汇和正确的机制。
Ask three questions: What is the organism? What system or process is involved? What is being changed or measured? For example, a runner whose breathing rate rises points to gas exchange and respiration, while a pond with fewer fish after fertiliser run-off points to eutrophication and food chains.
问三个问题：这是什么生物？涉及哪个系统或过程？什么被改变或被测量？例如，一名跑步者呼吸频率上升，指向气体交换与呼吸作用；而施肥后径流导致池塘鱼变少，则指向水体富营养化与食物链。
Common Year 7 topic links worth memorising: cells and microscopes, enzymes and digestion, breathing and heart rate, food chains and energy transfer, plant growth and photosynthesis, and reproduction and variation.
值得记住的七年级常见主题联系：细胞与显微镜、酶与消化、呼吸与心率、食物链与能量传递、植物生长与光合作用，以及生殖与变异。
6. Worked Example: Heart Rate and Exercise | 实战示例：心率与运动
Scenario: a pupil records her resting heart rate as 72 bpm. After two minutes of running, it is 110 bpm. After five minutes of rest, it returns to 76 bpm.
情境：一名学生测得静息心率为 72 bpm。跑两分钟后为 110 bpm。休息五分钟后恢复到 76 bpm。
A weak answer says 'her heart rate increased'. A strong answer says 'the heart rate increased from 72 bpm to 110 bpm, an increase of 38 bpm, because the working muscles need more oxygen and glucose for respiration, so the heart pumps faster to deliver them'.
弱答案只会说"她的心率上升了"。强答案会说："心率从 72 bpm 上升到 110 bpm，增加了 38 bpm，因为运动中的肌肉需要更多氧气和葡萄糖进行呼吸作用，所以心脏加快泵血来输送它们。"
Change in heart rate = 110 − 72 = 38 bpm
心率变化 = 110 − 72 = 38 bpm
If the question asks you to predict, use the recovery data: because the rate was falling by roughly 7 bpm per minute, it should be close to the resting value within about five more minutes.
如果题目要求预测，就利用恢复阶段的数据：由于心率大约每分钟下降 7 bpm，再过约五分钟就应接近静息值。
7. Worked Example: Food Chains and Energy Transfer | 实战示例：食物链与能量传递
nergy stored in each level: 20 000 kJ in the grass, 2 000 kJ in the rabbits, 200 kJ in the fox.
情境：一条草地食物链为 草 → 兔 → 狐狸。表格显示各营养级储存的能量：草 20 000 kJ，兔 2 000 kJ，狐狸 200 kJ。
The pattern is a tenfold loss at each step. Only about 10 % of the energy is passed on, because most is lost as heat from respiration, or remains in uneaten parts and undigested material.
规律是每一级损失十倍。只有约 10 % 的能量被传递下去，因为大部分以呼吸作用的热能散失，或留在未被吃掉的部分和未被消化的物质中。
Energy transfer efficiency = (energy in next level ÷ energy in previous level) × 100 %
能量传递效率 = （下一营养级的能量 ÷ 上一营养级的能量）× 100 %
Using the figures: (2 000 ÷ 20 000) × 100 % = 10 %, and (200 ÷ 2 000) × 100 % = 10 %. This explains why food chains rarely have more than four or five levels – there is simply not enough energy left to support another consumer.
代入数据：（2 000 ÷ 20 000）× 100 % = 10 %，（200 ÷ 2 000）× 100 % = 10 %。这就解释了为什么食物链很少超过四到五个营养级——剩下的能量根本不足以再支撑一个消费者。
8. Writing Full-Sentence Answers with Data | 用完整句子并结合数据作答
Markers reward precision. Use a simple three-part structure for every explanation: state, evidence, reason.
评分者奖励精确性。每个解释都用简单的三段式结构：结论、证据、原因。
- State the pattern clearly. 清晰陈述趋势。
- Quote the data with units and, where possible, the size of the change. 引用带单位的数据，并尽可能给出变化幅度。
- Give the biological reason using 'because'. 用"因为"给出生物学原因。
Compare these two answers. Weak: 'The plants grew more.' Strong: 'The plants in 0.1 % carbon dioxide grew 4.2 cm taller than those in 0.03 % carbon dioxide, because carbon dioxide is a reactant needed for photosynthesis, so more of it allows a faster rate of growth.'
比较这两个答案。弱答案："植物长得更多。"强答案："在 0.1 % 二氧化碳中生长的植物比在 0.03 % 二氧化碳中生长的植物高 4.2 cm，因为二氧化碳是光合作用所需的反应物，所以二氧化碳越多，生长速率越快。"
9. Avoiding Vague Language and Common Errors | 避免模糊表述与常见错误
Vague answers are the biggest single cause of lost marks in case study questions, because they cannot be credited even when the underlying idea is correct.
模糊答案是个案分析题失分的最大原因，因为即使背后的想法没错，也无法给分。
| Avoid | 避免 | Write instead | 改写为 |
| 'It increased.' | 'It increased from 12 cm³ to 19 cm³ in five minutes.' |
| 'Because it is better.' | 'Because more oxygen reaches the muscle cells for respiration.' |
| 'The enzyme died.' | 'The enzyme was denatured, so the active site changed shape.' |
| 'There was more stuff.' | 'The concentration of glucose rose by 0.5 mol dm⁻³.' |
Other frequent slips include describing the graph instead of explaining it, forgetting units, mixing up the terms 'rate' and 'amount', and writing about the wrong organism because the scenario was skimmed.
其他常见失误包括：只描述图表却不作解释、忘记写单位、混淆"速率"与"数量"，以及因粗略浏览情境而写错了生物对象。
10. Marks, Marking Schemes and Self-Assessment | 分值与评分标准：自我评估
Case study questions are marked with point marking, so each valid idea earns one mark. That means writing three clear, different points scores better than writing one long, repeated sentence.
案例分析题采用要点给分制，每个有效要点得一分。因此，写出三个清晰且不同的要点，比写一句冗长重复的话得分更高。
After every practice question, mark your own answer against the mark scheme and label each point S, E or R – statement, evidence, reason. Points you lose are almost always missing evidence or missing reasons, rarely missing knowledge.
每做完一道练习题，都对照评分标准给自己打分，并把每个要点标为 S、E 或 R——结论、证据、原因。你丢的分几乎总是缺少证据或原因，很少是因为缺少知识。
Keep an error log with three columns: the command word, what the mark scheme wanted, and what you actually wrote. Reviewing ten logged errors is worth more than answering ten new questions.
准备一个三列的错误日志：指令词、评分标准要求什么、你实际写了什么。复习十个已记录的错误，比再做十道新题更有价值。
11. Building a Case Study Routine | 建立案例分析训练流程
Skill in case studies comes from routine, not from last-minute cramming. A short, repeated cycle beats a long, occasional session.
案例分析的技能来自日常习惯，而不是临时抱佛脚。短而重复的循环胜过偶尔的长时段学习。
- Step 1 – Read the scenario twice and underline the data. 第一步——读两遍情境，划出数据。
- Step 2 – Highlight the command word and note how many marks are available. 第二步——标出指令词，并记下该题分值。
- Step 3 – Plan one bullet point per mark in the margin. 第三步——在页边按每分一个要点列出提纲。
- Step 4 – Write in full sentences, quoting data with units. 第四步——用完整句子作答，引用带单位的数据。
- Step 5 – Check units, spelling of scientific terms, and that you answered the question asked. 第五步——检查单位、科学术语拼写，并确认你回答了题目所问的内容。
Ten minutes of this routine, three times a week, is enough to make a visible difference within a term.
每周三次、每次十分钟按这个流程练习，一个学期内就能看到明显进步。
12. Exam-Day Checklist | 考试当天检查清单
On the day itself, discipline matters more than extra knowledge. Run through this checklist mentally before you turn the page.
到了考试当天，自律比额外知识更重要。翻开下一页之前，在脑中过一遍这份清单。
- Have I identified the command word? 我识别出指令词了吗？
- Have I quoted at least one piece of data with its unit? 我至少引用了一处带单位的数据吗？
- Does every explanation contain the word 'because' or an equivalent link? 每个解释里是否都有"因为"或等效的逻辑连接？
- Have I written one separate point for each available mark? 我是否针对每一分都写了一个独立要点？
- Have I checked for vague words such as 'more', 'better' or 'it'? 我是否检查了"更多""更好""它"这类模糊词？
Answer in full sentences, refer back to the data provided, and never leave a case study question blank – a partial statement plus a named biological process can still earn marks.
用完整句子作答，回扣所给数据，绝不留空白——一个部分正确的陈述加上一个准确的生物学过程，仍可能得分。
Published by TutorHao | Year 7 Biology Revision Series | aleveler.com
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