📚 Year 7 WJEC Science: Common Misconceptions and How to Correct Them | Year 7 WJEC 科学：常见误区与纠正方法
In Year 7 WJEC science lessons, students explore fascinating topics across biology, chemistry and physics. However, many learners arrive with ideas they have picked up from everyday life that do not match scientific understanding. These misconceptions can become barriers to deeper learning if left unchallenged. This article highlights ten of the most common misunderstandings in the Year 7 WJEC curriculum and explains how to correct them. By tackling these early, pupils can build a more secure foundation in science.
在 Year 7 WJEC 科学课堂上，学生们开始探索生物学、化学和物理学中有趣的主题。然而，许多学习者带着从日常生活中形成的、与科学理解不符的想法来到课堂。这些误区如果不被纠正，可能成为深入学习科学知识的障碍。本文列出了 Year 7 WJEC 课程中最常见的十个误解，并解释如何纠正它们。尽早解决这些问题，可以帮助学生建立更牢固的科学基础。
1. Plants Absorb Their Food from the Soil | 植物从土壤中吸收食物
A very common belief among Year 7 learners is that plants "eat" by taking food from the soil through their roots. They often think the soil itself is the plant's meal, like food for animals.
七年级学生中一个非常普遍的信念是：植物通过根部从土壤中吸收食物。他们常常认为土壤本身就是植物的“饭菜”，就像动物的食物一样。
In reality, plants make their own food through photosynthesis. They use sunlight, carbon dioxide from the air and water to produce glucose, which is their food. The soil provides water and mineral ions (such as nitrates and magnesium), but these are not the plant's food source.
实际上，植物通过光合作用自己制造食物。它们利用阳光、空气中的二氧化碳和水来生产葡萄糖，这才是它们的食物。土壤提供水分和矿物离子（如硝酸盐和镁离子），但这些并不是植物的食物来源。
Teachers can demonstrate this by growing plants in nutrient solution instead of soil, showing that the material comes from water and air, not the soil itself.
教师可以通过在营养液中而非土壤中种植植物来证明这一点，表明植物的物质来自水和空气，而不是土壤本身。
2. Only Animal Cells Have a Cell Membrane | 只有动物细胞才有细胞膜
Many students learn that plant cells have a cell wall and animal cells do not. From this, they often wrongly conclude that only animal cells possess a cell membrane. They sometimes imagine the cell wall acts as the boundary in plant cells.
许多学生知道植物细胞有细胞壁而动物细胞没有。由此，他们常常错误地推断只有动物细胞才有细胞膜。有时他们会想象细胞壁是植物细胞的边界。
All cells, whether animal, plant or bacterial, have a cell membrane. This structure controls which substances enter and leave the cell. In plant cells, the cell membrane is located just inside the cell wall. The cell wall provides extra support and shape, but it is the membrane that maintains the internal environment.
所有细胞，不论是动物、植物还是细菌，都具有细胞膜。这个结构控制着物质的进出。在植物细胞中，细胞膜紧贴在细胞壁的内侧。细胞壁提供额外的支撑和形状，但维持内部环境的是细胞膜。
Using a labelled diagram where both the cell wall and cell membrane are clearly shown helps pupils avoid this confusion.
使用清晰标注细胞壁和细胞膜的示意图，可以帮助学生避免这种混淆。
3. Heavier Objects Fall Faster Than Lighter Ones | 重的物体比轻的物体下落更快
From everyday experience, a stone seems to fall much faster than a feather. Year 7 pupils often generalise and believe that heavier objects always fall faster, even without air resistance.
从日常经验来看，石头似乎比羽毛下落得快得多。七年级学生常常将其一般化，认为重的物体总是下落得更快，即使在没有空气阻力的情况下也是如此。
In the absence of air resistance, all objects fall at the same rate regardless of their mass. This was famously demonstrated by astronauts dropping a hammer and a feather on the Moon. The difference on Earth is caused by air resistance, not by weight. Gravity pulls equally on every kilogram of mass.
在没有空气阻力的情况下，所有物体无论质量大小，都以相同的速率下落。航天员在月球上同时释放锤子和羽毛的著名实验证明了这一点。在地球上观察到差异是由空气阻力引起的，而非重量。重力对每千克质量施加同样的拉力。
Demonstrating this with two bottles of the same shape, one full of water and one empty, dropped simultaneously can help clarify that air resistance, not weight, is the key factor.
使用两个形状相同、一个装满水一个为空的瓶子同时下落，可以帮助学生澄清空气阻力而非重量才是关键因素。
4. Electric Current Gets Used Up in a Circuit | 电流在电路中被消耗掉了
Many learners think that electric current flows out of the battery and gradually gets "used up" by components such as bulbs, so that less current returns to the battery than left it.
许多学习者认为电流从电池流出，逐渐被灯泡等元件“消耗掉”，因此回到电池的电流比流出的少。
In a series circuit, electric current is the same at all points. Charge is conserved; it is never used up. What is transferred is energy, not current. The battery provides energy that is converted into light and heat in the bulb, but the moving charges continue around the entire loop.
在串联电路中，各处的电流大小都是相同的。电荷是守恒的，它永远不会被消耗掉。被转移的是能量而不是电流。电池提供能量，在灯泡中转化为光和热，但流动的电荷在整个环路中继续循环。
Using ammeters placed before and after a bulb in a simple circuit will show the same reading, powerfully challenging the misconception.
在简单电路中，将电流表放置在灯泡前后，会显示相同的读数，这强烈地反驳了这一误区。
5. There Is No Space Between Particles in a Solid | 固体中的粒子之间没有间隙
When drawing particle diagrams, pupils often draw solid particles packed so tightly that they touch with no gaps at all. This can lead to misunderstanding properties such as thermal expansion.
在绘制粒子图时，学生常将固体粒子画得紧密相连，完全没有空隙。这可能导致对热膨胀等性质的误解。
Even in solids, there are tiny spaces between particles. The particles are held in fixed positions by strong forces, but they are not actually touching. When a solid is heated, the particles vibrate more and these spaces increase slightly, causing the solid to expand.
即使在固体中，粒子之间也存在微小的间隙。粒子被强大的作用力固定在位置上，但它们实际上并不接触。当固体受热时，粒子振动加剧，这些间隙略微增大，导致固体膨胀。
A model using marbles in a tray on an overhead projector—when shaken, the marbles move apart slightly—illustrates this expansion without the marbles themselves changing size.
使用在投影仪上托盘中的弹珠模型——当摇晃时，弹珠稍微分开——可以说明这种膨胀，而弹珠本身大小并未改变。
6. Energy Gets Used Up and Disappears | 能量耗尽了，消失了
In everyday language we talk about "using up energy" in a battery or in our bodies. Year 7 pupils often transfer this idea to the scientific model and believe energy literally vanishes.
在日常用语中，我们会说电池或身体“耗尽了能量”。七年级学生经常将这种想法转移到科学模型中，相信能量真的会消失。
Energy is never used up or destroyed. It is conserved and transferred to other stores or pathways. For example, a torch battery transfers chemical energy electrically to the bulb, where it is transferred by radiation (light) and heating (thermal) to the surroundings.
能量永远不会被耗尽或消灭。它是守恒的，被转移到其他的能量储存库或途径中去。例如，手电筒电池将化学能以电的方式转移到灯泡，在灯泡中通过辐射（光能和热能）转移到周围环境。
A simple energy transfer diagram like "chemical store → electrical pathway → thermal store of surroundings + radiation pathway" can reinforce the idea of conservation.
一个简单的能量转移图，如“化学能储存 → 电能途径 → 周围环境的热能储存 + 辐射途径”，可以强化能量守恒的概念。
7. Breathing and Respiration Are the Same Thing | 呼吸和呼吸作用是一回事
This is a very persistent linguistic misconception. Pupils use the word "respiration" to mean the physical process of inhaling and exhaling air, as it sounds similar to "breathing".
这是一个非常顽固的语言误区。学生使用“呼吸作用”一词来指代吸气和呼气的物理过程，因为它听起来与“呼吸”相似。
Breathing is the mechanical movement of air into and out of the lungs. Respiration is a chemical reaction that occurs inside cells, releasing energy from glucose. Respiration happens all the time in all living cells, even when a person is not visibly breathing in and out.
呼吸是空气进出肺部的机械运动。呼吸作用是在细胞内发生的化学反应，从葡萄糖中释放能量。呼吸作用在所有活细胞中持续发生，即使人没有明显的吸气和呼气动作。
The summary equation for aerobic respiration is:
glucose + oxygen → carbon dioxide + water (+ energy released)
有氧呼吸的总方程式为：
葡萄糖 + 氧气 → 二氧化碳 + 水（+ 释放的能量）
Using a word equation and emphasising that it takes place in mitochondria helps distinguish it from the movement of the ribcage.
使用文字方程式，并强调该过程发生在线粒体中，有助于将其与胸腔的运动区分开来。
8. The Moon Produces Its Own Light | 月亮自身会发光
When observing the night sky, the Moon appears to shine brightly. Young learners often believe the Moon is a luminous source, just like the Sun or a light bulb.
观察夜空时，月亮看起来明亮地闪耀着。年幼的学习者经常相信月亮是一个光源，就像太阳或灯泡一样。
The Moon is a non-luminous object; it does not produce its own light. We see the Moon because it reflects light from the Sun. The different phases of the Moon are caused by the relative positions of the Earth, Moon and Sun, changing how much of the sunlit side we see.
月亮是一个非发光体，它自身不产生光。我们看到月亮是因为它反射了来自太阳的光。月相的不同是由于地球、月亮和太阳的相对位置变化，改变了我们看到被太阳照亮一侧的多少。
Modelling this with a torch and a ball in a darkened room can effectively correct the misunderstanding.
在黑暗的房间中用手电筒和球进行建模，可以有效地纠正这一误解。
9. All Acids Are Dangerous and All Alkalis Are Safe | 所有酸都是危险的，所有碱都是安全的
From warning symbols on cleaning products, pupils sometimes develop the idea that all acids are harmful while alkalis are harmless. They may not realise many everyday substances are acidic or alkaline.
从清洁产品上的警告标志，学生有时会形成所有酸都是有害的、而所有碱都是无害的想法。他们可能没有意识到许多日常物质是酸性或碱性的。
Both acids and alkalis can be corrosive and harmful depending on their concentration. Weak acids like citric acid in lemons and weak alkalis like sodium hydrogen carbonate (baking soda) are safe to handle. Even concentrated alkalis can cause severe burns. The pH scale, from 0 to 14, helps us measure how acidic or alkaline a substance is, with 7 being neutral.
酸和碱根据其浓度都可能具有腐蚀性和危害性。柠檬中的柠檬酸等弱酸和碳酸氢钠（小苏打）等弱碱可以安全处理。即使是浓缩的碱也会造成严重烧伤。pH 值范围从 0 到 14，帮助我们测量物质的酸碱性，7 为中性。
Hands-on testing with universal indicator and household items reinforces the concept that being acidic or alkaline does not automatically equal dangerous.
使用通用指示剂和家用物品进行动手实验，强化了酸性或碱性并不自动等于危险的概念。
10. All Metals Are Magnetic | 所有金属都有磁性
Because fridge magnets often stick to metals, many Year 7 pupils think that if something is made of metal, a magnet will attract it. They group all metals together as magnetic.
因为冰箱磁贴通常能粘住金属，许多七年级学生认为只要是金属制成的东西，磁铁就会吸引它。他们将所有金属都归为有磁性的。
Only certain metals, such as iron, nickel and cobalt, are magnetic. Most other metals, including aluminium, copper, zinc, gold and silver, are not attracted to magnets. A magnet picking up an iron nail but not a copper coin is a simple demonstration that clears up this myth.
只有某些金属，如铁、镍和钴，是带有磁性的。大多数其他金属，包括铝、铜、锌、金和银，不会吸引磁铁。磁铁能吸起铁钉而不能吸起铜币的简单演示，可以澄清这个误区。
It is also important to note that steel, an alloy containing iron, is magnetic, which is why many everyday "metal" objects stick to magnets.
还需要注意的是，钢是含有铁的合金，具有磁性，这就是为什么许多日常“金属”物品能粘在磁铁上。
11. Digestion Only Happens in the Stomach | 消化只发生在胃里
When studying the human body, learners often imagine that food travels down to the stomach and is digested there, with the intestines simply being a tube to get rid of waste.
在学习人体时，学习者经常想象食物向下移动到胃，并在那里被消化，而肠道仅仅是一个排除废物的管子。
Digestion is a process that begins in the mouth, where teeth break down food mechanically and enzymes in saliva start to break down starch chemically. It continues in the stomach, but most chemical digestion and absorption of nutrients occurs in the small intestine. The large intestine absorbs water and forms faeces.
消化是一个从口腔就开始的过程，牙齿通过机械方式粉碎食物，唾液中的酶开始化学分解淀粉。这一过程在胃里继续进行，但绝大多数的化学消化和营养吸收发生在小肠。大肠吸收水分并形成粪便。
Tracing the path of a banana sandwich through the digestive system with labelled diagrams can help embed the correct sequence and functions.
通过带标注的示意图追踪一个香蕉三明治在消化系统中的路径，有助于记住正确的顺序和功能。
Published by TutorHao | Science Revision Series | aleveler.com
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