📚 KS3 CIE Ecosystems Sentence Completion Mark Scheme | KS3 CIE 生态系统句子填空题评分标准
In CIE KS3 Science, ecosystems questions often use sentence completion to test precise scientific vocabulary. This article explains how to answer these items and how marks are awarded, with examples based on typical CIE mark schemes.
在 CIE KS3 科学考试中，生态系统题目常通过句子填空来考查准确的科学词汇。本文解释如何作答以及评分标准如何给分，并提供基于典型 CIE 评分标准的示例。
1. What Are Sentence Completion Questions? | 什么是句子填空题？
A sentence completion question gives a statement with one or more missing words. You must choose or write the correct scientific term so the sentence is true and matches the syllabus.
句子填空题给出一句带有空缺词语的陈述。你必须选择或写出正确的科学术语，使句子完整、正确并符合大纲要求。
In CIE KS3 Ecosystems, these items often target definitions, processes, or relationships between organisms. One mark is usually awarded for each correct term.
在 CIE KS3 生态系统中，这类题目通常考查定义、过程或生物之间的关系。每个正确术语通常得 1 分。
2. Why the Mark Scheme Matters | 为什么评分标准很重要？
The mark scheme shows the exact answers examiners accept. It may include alternatives, reject common wrong answers, and state whether spelling must be correct.
评分标准列出考官接受的准确答案。它可能包含可接受的替代词、排除常见错误答案，并说明拼写是否必须正确。
For sentence completion, you are usually expected to use one word or a short phrase. Extra words can invalidate an otherwise correct answer.
对于填空题，通常要求只写一个词或短语。多余的文字可能使原本正确的答案无效。
3. Core Ecosystem Vocabulary | 生态系统核心词汇
The most common terms include habitat, population, community, ecosystem, producer, consumer, decomposer, herbivore, carnivore, omnivore, predator and prey.
最常见的术语包括栖息地、种群、群落、生态系统、生产者、消费者、分解者、植食动物、肉食动物、杂食动物、捕食者和猎物。
| Term | Definition | 中文释义 |
|---|---|---|
| Population | All organisms of the same species living in the same area | 同一区域内同一物种的所有个体 |
| Community | All populations of different species living together in an area | 同一区域内不同物种的所有种群 |
| Ecosystem | A community of organisms interacting with their abiotic environment | 生物群落与其非生物环境相互作用的系统 |
| Habitat | The place where an organism lives | 生物生活的场所 |
Always check whether the sentence refers to one species or many species, because this is how examiners separate population from community.
始终要检查句子是指一个物种还是多个物种，因为考官正是借此区分 "population" 和 "community"。
4. Food Chains and Food Webs | 食物链与食物网
A food chain shows the transfer of energy from one organism to another. The arrows show the direction of energy flow, not who eats whom.
食物链显示能量从一个生物传递到另一个生物。箭头表示能量流动的方向，而不是谁吃谁。
Typical sentence completion: "In a food chain, the producer is eaten by the primary __________." Answer: consumer. Another: "An organism that breaks down dead material is called a __________." Answer: decomposer.
典型填空题："在食物链中，生产者被初级__________所食。" 答案：consumer。另一题："分解死亡物质的生物称为__________。" 答案：decomposer。
5. Energy Flow and Trophic Levels | 能量流动与营养级
Energy enters most ecosystems as sunlight. Green plants capture it by photosynthesis and store it as chemical energy in biomass.
能量以阳光形式进入大多数生态系统。绿色植物通过光合作用捕获能量，并将其以化学能形式储存在生物量中。
At each trophic level, energy is lost as heat through respiration, movement and undigested food. On average, only about 10% of energy is passed on to the next level.
在每一个营养级，能量通过呼吸作用、运动以及未被消化的食物以热能形式散失。平均只有约 10% 的能量传递到下一营养级。
