📚 Year 10 WJEC Science: Core Knowledge Consolidation | Year 10 WJEC 科学：核心知识点梳理
The Year 10 WJEC Science course builds the essential foundation for GCSE success by weaving together key concepts from biology, chemistry and physics. This article brings together the core knowledge every student must master – from cell structure and chemical bonding to forces, electricity and ecosystems – to ensure a solid understanding for further study and examinations.
Year 10 WJEC 科学课程将生物、化学和物理的核心概念融为一体，为 GCSE 的成功奠定了必要基础。本文梳理了每位学生必须掌握的关键知识，从细胞结构、化学键到力、电学和生态系统，以确保对进一步学习和考试有扎实的理解。
1. Cell Biology | 细胞生物学
All living organisms are made of cells, which are the basic structural and functional units of life. Cells can be classified as prokaryotic (e.g. bacteria) or eukaryotic (e.g. plant and animal cells). Eukaryotic cells contain a true nucleus and membrane-bound organelles, whereas prokaryotic cells have no nucleus and their genetic material floats freely in the cytoplasm.
所有生物都由细胞组成，细胞是生命的基本结构和功能单位。细胞可分为原核细胞（如细菌）和真核细胞（如植物和动物细胞）。真核细胞含有真正的细胞核和膜包被的细胞器，而原核细胞没有细胞核，其遗传物质在细胞质中自由漂浮。
Animal cells typically possess a cell membrane, cytoplasm, nucleus, mitochondria and ribosomes. Plant cells share these structures but also contain a rigid cell wall, a large permanent vacuole and chloroplasts that enable photosynthesis. The table below compares their key organelles.
动物细胞通常具有细胞膜、细胞质、细胞核、线粒体和核糖体。植物细胞也有这些结构，但另外含有坚硬的细胞壁、一个大型永久液泡以及可以进行光合作用的叶绿体。下表比较了它们的关键细胞器。
| Organelle | Animal Cell | Plant Cell |
|---|---|---|
| Nucleus | Present | Present |
| Cytoplasm | Present | Present |
| Cell membrane | Present | Present |
| Mitochondria | Present | Present |
| Ribosomes | Present | Present |
| Cell wall | Absent | Present (made of cellulose) |
| Chloroplasts | Absent | Present |
| Permanent vacuole | Absent (small temporary vacuoles may occur) | Present (large, central) |
Cells can become specialised to perform specific functions. For example, red blood cells have no nucleus to maximise space for haemoglobin, sperm cells have a streamlined head and a long tail for movement, and root hair cells possess a large surface area to absorb water and minerals efficiently.
细胞可以特化以执行特定功能。例如，红细胞没有细胞核以最大限度地容纳血红蛋白，精子细胞具有流线型的头部和用于运动的长尾，根毛细胞拥有较大的表面积以高效吸收水分和矿物质。
Microscopy allows us to observe cells. A light microscope uses visible light and lenses to magnify specimens, whereas an electron microscope uses a beam of electrons for much higher magnification and resolution. The magnification of a light microscope is calculated using the formula:
显微镜使我们能够观察细胞。光学显微镜使用可见光和透镜来放大标本，而电子显微镜使用电子束获得更高的放大倍数和分辨率。光学显微镜的放大率可使用以下公式计算：
Magnification = Image size / Actual size
Substances move across cell membranes by diffusion (movement of particles from high to low concentration down a concentration gradient), osmosis (the diffusion of water across a partially permeable membrane) and active transport (movement against a concentration gradient using energy from respiration). These processes are vital for nutrient uptake and waste removal.
物质通过扩散（粒子沿浓度梯度从高浓度向低浓度移动）、渗透（水通过部分渗透膜的扩散）和主动运输（利用呼吸作用产生的能量逆浓度梯度移动）穿过细胞膜。这些过程对于营养吸收和废物清除至关重要。
2. Atomic Structure and the Periodic Table | 原子结构与周期表
d by negatively charged electrons arranged in shells. The relative masses are: proton ≈ 1, neutron ≈ 1, electron ≈ 1/1836. The atomic number (Z) is the number of protons, which determines the element; the mass number (A) is the total number of protons and neutrons.
所有物质都由原子构成。原子由一个微小的、致密的核组成，核内有带正电的质子和不带电的中子，核外电子在电子层上排列。相对质量为：质子 ≈ 1，中子 ≈ 1，电子 ≈ 1/1836。原子序数（Z）是质子数，它决定了元素种类；质量数（A）是质子与中子的总数。
Isotopes are atoms of the same element with the same number of protons but different numbers of neutrons. They have identical chemical properties because they have the same electron configuration, but their physical properties, such as density and rate of diffusion, may differ slightly.
同位素是具有相同质子数但中子数不同的同一元素的原子。由于它们具有相同的电子排布，因此化学性质相同；但物理性质如密度和扩散速率可能略有不同。
Electrons fill shells in a 2,8,8 pattern for the first 20 elements. The group number in the periodic table tells you how many electrons are in the outer shell (for Groups 1, 2, 13–18 adjusted as 1, 2, 3–8). The period number gives the number of occupied electron shells. Elements in the same group have similar chemical reactions because they have the same number of outer electrons.
前20号元素的电子按2,8,8规律填充电子层。元素周期表中的族序数可告诉最外层电子数（第1、2、13–18族分别对应1、2、3–8个电子）。周期数表示电子层的数目。同一主族元素具有相似的化学反应，因为它们具有相同的最外层电子数。
The periodic table arranges elements in order of increasing atomic number. Metals are found on the left and centre, non-metals on the right. Group 1 contains the alkali metals (very reactive, form 1⁺ ions), Group 7 the halogens (reactive non-metals, form 1⁻ ions), and Group 0 the noble gases (unreactive, have a full outer shell).
元素周期表按原子序数递增排列元素。金属位于左侧和中部，非金属在右侧。第1族包含碱金属（反应性强，形成1⁺离子），第7族是卤素（反应性非金属，形成1⁻离子），第0族是稀有气体（不活泼，具有全满最外层电子）。
3. Bonding and Structure | 键合与结构
Atoms bond together to achieve a more stable electron arrangement, often attaining a full outer shell like a noble gas. The three main types of strong chemical bonding are ionic, covalent and metallic.
原子之间通过键合获得更稳定的电子排布，通常达到类似稀有气体的全满最外层。三种主要的化学键类型是离子键、共价键和金属键。
Ionic bonding involves the transfer of electrons from a metal to a non-metal. The metal atom loses electrons to become a positive ion (cation), while the non-metal gains those electrons to become a negative ion (anion). The oppositely charged ions are held together by strong electrostatic forces in a giant ionic lattice. Ionic compounds have high melting and boiling points and conduct electricity when molten or dissolved because the ions are free to move.
离子键涉及电子从金属转移到非金属。金属原子失去电子形成正离子（阳离子），非金属原子获得电子形成负离子（阴离子）。带相反电荷的离子通过强大的静电作用力聚集在巨大的离子晶格中。离子化合物熔点、沸点高，在熔融或溶解状态下可以导电，因为此时离子可以自由移动。
Covalent bonding forms when non-metal atoms share pairs of electrons. Covalent substances can be simple molecular (e.g. H₂O, CO₂, O₂) with low melting and boiling points due to weak intermolecular forces, or giant covalent structures (e.g. diamond, graphite, SiO₂) with very high melting points because many strong covalent bonds must be broken. Graphite conducts electricity thanks to delocalised electrons between layers.
共价键由非金属原子共用电子对而形成。共价物质可以是简单分子（例如H₂O、CO₂、O₂），由于分子间作用力较弱，熔沸点较低；也可以是巨型共价结构（如金刚石、石墨、SiO₂），因为必须破坏大量强共价键，因而熔点很高。石墨由于层间拥有离域电子而能够导电。
Metallic bonding occurs between metal atoms. The atoms form a regular lattice and their outer electrons become delocalised, creating a "sea" of electrons that can move freely. This gives metals their characteristic properties: high electrical and thermal conductivity, malleability and ductility.
金属键存在于金属原子之间。原子排列成规则晶格，外层电子离域形成能够自由移动的电子“海洋”。这赋予了金属独特的性质：良好的导电性和导热性、延展性和可塑性。
4. Quantitative Chemistry | 定量化学
Quantitative chemistry enables us to calculate amounts of substances involved in chemical reactions. The relative atomic mass (Aᵣ) is an average mass of an atom of an element compared to 1/12th the mass of a carbon‑12 atom. The relative formula mass (Mᵣ) is the sum of the Aᵣ of all atoms in the formula unit.
定量化学使我们能够计算参与化学反应的物质的质量。相对原子质量（Aᵣ）是指某元素一个原子的平均质量与一个碳‑12原子质量的1/12的比值。相对式量（Mᵣ）是化学式中所有原子Aᵣ的总和。
The law of conservation of mass states that no atoms are lost or made during a chemical reaction, so the total mass of reactants equals the total mass of products. This is why chemical equations must be balanced.
质量守恒定律表明，在化学反应中原子既不会消失也不会凭空产生，因此反应物的总质量等于生成物的总质量。这就是化学方程式必须配平的原因。
or amount of substance. One mole of any substance contains 6.02 × 10²³ particles (Avogadro' mole of a substance is its Mᵣ expressed in grams. The number of moles can be found using:
摩尔是物质的量的单位。1摩尔任何物质都含有6.02 × 10²³个微粒（阿伏伽德罗常数）。1摩尔物质的质量在数值上等于其Mᵣ，以克为单位。摩尔数可用下式求得：
n = m / Mᵣ
where n is the number of moles, m is the mass in grams, and Mᵣ is the relative formula mass. The concentration of a solution in g/dm³ can be calculated by dividing the mass of solute by the volume of solution in dm³.
其中n为摩尔数，m为质量（克），Mᵣ为相对式量。溶液的浓度（g/dm³）可以通过溶质质量除以溶液体积（dm³）来计算。
5. Energy in Reactions and Energy Resources | 反应中的能量与能源
Chemical reactions can be exothermic or endothermic. Exothermic reactions transfer energy to the surroundings, causing a temperature rise (e.g. combustion, neutralisation). Endothermic reactions take in energy from the surroundings, causing a temperature drop (e.g. thermal decomposition, photosynthesis).
化学反应可以是放热或吸热的。放热反应向周围环境释放能量，导致温度升高（例如燃烧、中和反应）。吸热反应从周围环境吸收能量，导致温度下降（例如热分解、光合作用）。
Energy profile diagrams show the energy change during a reaction. In an exothermic profile the products have less energy than the reactants (ΔH is negative); in an endothermic profile the products have more energy (ΔH is positive). The activation energy is the minimum energy needed for colliding particles to react.
能量变化图显示了反应过程中的能量变化。在放热反应曲线中，生成物的能量低于反应物（ΔH为负值）；在吸热反应曲线中，生成物的能量更高（ΔH为正值）。活化能是反应物粒子碰撞发生反应所需的最低能量。
Overall energy change can be calculated from bond energies: energy required to break bonds (endothermic) minus energy released when forming bonds (exothermic). If more energy is released than absorbed, the reaction is exothermic overall.
总能量变化可以用键能计算：断裂化学键吸收的能量（吸热）减去形成化学键释放的能量（放热）。如果释放的能量多于吸收的能量，反应总体为放热。
Energy resources are classified as renewable (solar, wind, tidal, hydroelectric, geothermal, biomass) and non‑renewable (fossil fuels and nuclear). Power stations burn fuels to heat water, produce steam that drives a turbine connected to a generator. Efficiency of a device compares useful output energy to total input energy.
能源分为可再生能源（太阳能、风能、潮汐能、水力、地热、生物质能）和不可再生能源（化石燃料与核能）。发电站通过燃烧燃料加热水，产生蒸汽驱动与发电机相连的涡轮。设备的效率是指有用的输出能量与总输入能量之比。
6. Forces and Motion | 力与运动
Quantities in physics are either scalar (magnitude only, e.g. speed, distance, mass) or vector (magnitude and direction, e.g. velocity, displacement, force). A force can change the shape, speed or direction of an object. When the resultant force on an object is zero, the object remains stationary or continues moving at a constant speed in a straight line (Newton's First Law).
物理学中的量分为标量（仅有大小，如速率、路程、质量）和矢量（既有大小又有方向，如速度、位移、力）。力可以改变物体的形状、速度或方向。当作用在物体上的合力为零时，物体会保持静止或沿直线匀速运动（牛顿第一定律）。
Acceleration is the rate of change of velocity. Newton' tant force = mass × acceleration (F = m a). The acceleration due to gravity near the Earth' .8 m/s²). Speed (m/s) can be calculated as distance ÷ time, and the gradient of a distance–time graph gives speed.
加速度是速度随时间的变化率。牛顿第二定律表明合力 = 质量 × 加速度（F = m a）。地球表面附近的重力加速度约为10 m/s²（或9.8 m/s²）。速率（m/s）可用距离 ÷ 时间计算，距离‑时间图的斜率代表速率。
A velocity‑ e of a vehicle is the sum of thinking distance (reaction time × speed) and braking distance. Braking distance increases with speed squared and is affected by road conditions and tyre tread.
速度‑时间图可以提供更多信息：斜率代表加速度，图下面积代表位移。车辆的停车距离是反应距离（反应时间 × 速度）与刹车距离之和。刹车距离随速度的平方增大，还受路面状况和胎纹影响。
7. Electricity | 电学
Electric current is the rate of flow of charge. Current (I, in amperes) is measured with an ammeter placed in series. Potential difference (V, in volts) is the energy transferred per unit charge and is measured with a voltmeter placed in parallel. Resistance (R, in ohms, Ω) opposes the flow of current.
电流是电荷流动的速率。电流（I，单位安培）用串联在电路中的安培表测量。电势差（V，单位伏特）是单位电荷转移的能量，用并联的伏特表测量。电阻（R，单位欧姆，Ω）阻碍电流流动。
Ohm' ance of fixed resistors does not change, whereas the resistance of a filament lamp increases with temperature, and a diode only allows current to flow in one direction. In a series circuit the current is the same everywhere and the total resistance is the sum of individual resistances, while the supply voltage is shared across components. In a parallel circuit the voltage across each branch is the same as the supply voltage, and the total current is the sum of the currents in each branch.
欧姆定律指出，在温度恒定时，电阻两端的 V = I R。固定电阻器的电阻不变；而灯丝的电阻随温度升高而增大；二极管只允许电流单向流动。在串联电路中，电流处处相等，总电阻为各电阻之和，电源电压由各元件分担。在并联电路中，各支路两端电压与电源电压相同，总电流等于各支路电流之和。
| Property | Series Circuit | Parallel Circuit |
|---|---|---|
| Current (I) | Same everywhere | Splits across branches |
| Voltage (V) | Shared across components | Same across each branch |
| Resistance (R) | Rtotal = R₁ + R₂ + ... | 1/Rtotal = 1/R₁ + 1/R₂ + ... |
The National Grid transmits electricity at high voltages to reduce energy losses as heat.
电功率（P）是能量转移的速率，使用公式 P = I V 或 P = I² R 计算。总的能量转移可用 E = P t = I V t 求得。英国国家电网以高电压传输电能，以减少输电过程中的热损耗。
8. Waves | 波
Waves transfer energy from one place to another without transferring matter. Transverse waves, such as light and water waves, have oscillations perpendicular to the direction of energy transfer. Longitudinal waves, such as sound waves, have oscillations parallel to the direction of energy transfer and consist of compressions and rarefactions.
波将能量从一处传递到另一处而不传递物质。横波（如光波和水波）的振动方向与能量传递方向垂直。纵波（如声波）的振动方向与能量传递方向平行，由压缩和稀疏区域构成。
The key properties of a wave are amplitude (maximum displacement from rest position), wavelength (λ,
Published by TutorHao | Year 10 Science 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