📚 Animal Cells and Plant Cells: Shared Features | A-Level 生物：动物细胞与植物细胞的共同特征
Cells are the fundamental units of life, and despite the obvious differences between animals and plants, their cells share a remarkable set of structural and functional features. Understanding these common features is essential for grasping how life operates at the cellular level and forms the basis of many A-level biology questions.
细胞是生命的基本单位。尽管动物与植物之间存在明显差异，但它们的细胞却共享着一系列惊人的结构和功能特征。理解这些共同特征，是掌握细胞层面生命活动规律的关键，也是A-Level生物考试中许多题目的基础。
1. The Plasma Membrane: A Universal Boundary | 细胞膜：万物的边界
Both animal and plant cells possess a plasma membrane (also called the cell surface membrane) that encloses the cytoplasm and separates the cell's internal environment from the external surroundings. It is a phospholipid bilayer embedded with proteins, following the fluid mosaic model.
动物细胞和植物细胞都拥有细胞膜（又称细胞表面膜），它将细胞质包裹在内，将细胞的内部环境与外部环境分隔开来。细胞膜以磷脂双分子层为基本骨架，镶嵌着蛋白质，遵循“流动镶嵌模型”。
The membrane is selectively permeable — it controls which substances enter and leave the cell, allowing nutrient uptake and waste removal.
细胞膜具有选择性通透性——它控制哪些物质可以进出细胞，从而保证营养物质的吸收和废物的排出。
Membrane proteins perform vital roles: transport proteins move molecules across the membrane, receptor proteins detect chemical signals, and enzymes may be attached for metabolic reactions.
膜蛋白执行着重要的功能：转运蛋白负责跨膜运输分子，受体蛋白识别化学信号，一些酶也附着在膜上参与代谢反应。
In both cell types, the plasma membrane is the outermost boundary. In plant cells, it lies just inside the cell wall, but the wall is not a living component — the membrane remains the functional barrier.
在两类细胞中，细胞膜都是最外层的活性边界。在植物细胞中，细胞膜紧贴在细胞壁内侧，但细胞壁并非活性成分，细胞膜始终承担着功能性屏障的作用。
2. Cytoplasm: The Site of Cellular Activity | 细胞质：细胞活动的舞台
The cytoplasm is the gel-like substance that fills the cell, comprising the cytosol (the liquid component), organelles, and various inclusions. It is present in both animal and plant cells, occupying the space between the plasma membrane and the nucleus.
细胞质是填充于细胞内的胶状物质，由细胞质基质（液态成分）、细胞器和各种包含物组成。它存在于动物细胞和植物细胞中，占据细胞膜与细胞核之间的区域。
The cytosol is mostly water, but it also contains dissolved ions, small metabolites, and soluble enzymes. It supports the organelles and allows the diffusion of molecules.
细胞质基质主要由水构成，同时也溶解着离子、小分子代谢物和可溶性酶。它为细胞器提供支撑，并允许分子在其中的扩散。
Many metabolic reactions occur in the cytoplasm, including the early stages of respiration (glycolysis) and protein synthesis (translation). This means that in both cell types, the cytoplasm is a major site of biochemical activity.
许多代谢反应发生在细胞质中，包括呼吸作用的早期阶段（糖酵解）和蛋白质合成（翻译）。也就是说，在两类细胞中，细胞质都是生化活动的主要场所。
The cytoplasm also serves as a transport medium — substances move from one part of the cell to another via the cytosol, either by diffusion or with the aid of the cytoskeleton.
细胞质还充当着运输介质——物质通过细胞质基质在细胞的不同部位之间移动，这种方式既可以是自由扩散，也可以借助细胞骨架来完成。
3. Nucleus: The Control Centre | 细胞核：控制中心
Both animal and plant cells possess a well-defined nucleus, which is the largest organelle in most cells. The nucleus houses the genetic material (DNA) and coordinates cellular activities such as metabolism, growth, and reproduction.
动物细胞和植物细胞都拥有一个完整的细胞核，它是大多数细胞中最大的细胞器。细胞核内含有遗传物质（DNA），并协调着代谢、生长和繁殖等细胞活动。
The nucleus is surrounded by a double membrane called the nuclear envelope, which contains nuclear pores. These pores allow the transport of mRNA and ribosomes from the nucleus to the cytoplasm.
细胞核由双层核膜包裹，核膜上分布着核孔。这些核孔允许mRNA和核糖体从细胞核转运至细胞质。
Inside the nucleus, DNA is associated with histone proteins to form chromatin. During cell division, chromatin condenses into visible chromosomes, a process identical in both cell types.
在细胞核内部，DNA与组蛋白结合形成染色质。在细胞分裂期间，染色质凝聚为可见的染色体，这一过程在两类细胞中完全相同。
The nucleolus, a dense region within the nucleus, is responsible for synthesising ribosomal RNA (rRNA) and assembling ribosome subunits. Both animal and plant cells rely on this process to produce ribosomes.
核仁是细胞核内一个致密的区域，负责合成核糖体RNA（rRNA）并组装核糖体亚基。动物细胞和植物细胞都依赖这一过程来生产核糖体。
4. Ribosomes: Universal Protein Factories | 核糖体：通用的蛋白质工厂
Ribosomes are small, dense organelles found in enormous numbers in both animal and plant cells. They are the sites of protein synthesis, translating mRNA into polypeptide chains. This is one of the most fundamental shared features of all living cells.
核糖体是微小而致密的细胞器，在动物细胞和植物细胞中都以惊人的数量存在。它们是蛋白质合成的场所，将mRNA翻译成多肽链。这是所有活细胞中最基本、最普遍的共同特征之一。
Each ribosome is composed of two subunits (small and large), themselves made of rRNA and proteins. The subunits are assembled in the nucleolus and transported to the cytoplasm through nuclear pores.
每个核糖体由大、小两个亚基组成，而亚基本身又由rRNA和蛋白质构成。这些亚基在核仁中组装，再通过核孔运输至细胞质中。
Ribosomes may be free in the cytoplasm or bound to the rough endoplasmic reticulum (RER). Free ribosomes synthesise proteins that function within the cytoplasm, while bound ribosomes produce proteins destined for secretion or for membrane insertion.
核糖体既可以游离于细胞质中，也可以附着在粗面内质网上。游离核糖体负责合成在细胞质内发挥功能的蛋白质，而附着核糖体则合成用于分泌或插入细胞膜的蛋白质。
The process of translation — mRNA being read by ribosomes to assemble amino acids into proteins — is identical in animal and plant cells, highlighting the unity of molecular biology across eukaryotic organisms.
翻译过程——即核糖体读取mRNA将氨基酸组装成蛋白质——在动物细胞和植物细胞中完全相同，这凸显了整个真核生物在分子生物学上的统一性。
5. Mitochondria: The Powerhouses | 线粒体：细胞的动力站
Mitochondria are double-membrane-bound organelles present in both animal and plant cells. They are the primary sites of aerobic respiration, specifically the Krebs cycle and oxidative phosphorylation, which generate ATP — the cell's energy currency.
线粒体是双层膜细胞器，在动物细胞和植物细胞中均有分布。它们是有氧呼吸的主要场所，特别是三羧酸循环和氧化磷酸化这两个阶段，这些过程产生ATP——细胞的能量通货。
The inner mitochondrial membrane is folded into cristae, which greatly increase the surface area for the electron transport chain and ATP synthase enzymes. This structural feature is the same in both cell types.
线粒体内膜折叠形成嵴，极大地增加了电子传递链和ATP合酶的附着面积。这种结构特征在两类细胞中是相同的。
The matrix, the space enclosed by the inner membrane, contains enzymes for the Krebs cycle, along with mitochondrial DNA (mtDNA) and ribosomes. These enable mitochondria to synthesise some of their own proteins.
基质是内膜所围成的空间，其中含有三羧酸循环所需的酶，同时也含有线粒体DNA（mtDNA）和核糖体。这些成分使线粒体能够自主合成自身的一部分蛋白质。
In animal cells, mitochondria are plentiful in metabolically active tissues such as muscle and liver. In plant cells, mitochondria exist alongside chloroplasts but remain essential for respiration at night and in non-photosynthetic tissues.
在动物细胞中，肌肉和肝脏等代谢活跃的组织含大量线粒体。在植物细胞中，线粒体与叶绿体并存，但在夜间和无光合作用的组织中，线粒体仍然是必需的呼吸作用场所。
6. Endoplasmic Reticulum and Golgi Apparatus: The Synthesis and Transport System | 内质网与高尔基体：合成与运输体系
Both animal and plant cells possess an extensive endomembrane system, including the rough and smooth endoplasmic reticulum (RER and SER) and the Golgi apparatus. These organelles work together to synthesise, modify, package, and transport proteins and lipids.
动物细胞和植物细胞都拥有发达的内膜系统，包括粗面内质网、滑面内质网和高尔基体。这些细胞器协同工作，完成蛋白质和脂质的合成、修饰、包装与运输。
The RER is studded with ribosomes and is involved in protein synthesis and folding. Newly made proteins enter the RER lumen, where they are folded and modified before being transported to the Golgi apparatus.
粗面内质网表面布满核糖体，参与蛋白质的合成与折叠。新合成的蛋白质进入粗面内质网腔，在那里折叠并经过修饰，随后被运往高尔基体。
The SER lacks ribosomes and is responsible for lipid synthesis, including phospholipids and steroids. In both cell types, SER activity varies with cell type — for example, it is more extensive in cells that produce steroid hormones.
滑面内质网没有核糖体附着，主要负责脂质合成，包括磷脂和类固醇。在两类细胞中，滑面内质网的发达程度随细胞类型而异——例如，在产生类固醇激素的细胞中更为发达。
The Golgi apparatus consists of a stack of flattened membrane sacs called cisternae. It receives vesicles from the ER, modifies their contents, and packages them into vesicles for secretion or for delivery to other organelles.
高尔基体由一摞扁平的膜囊（称为潴泡）堆叠而成。它接收来自内质网的囊泡，对内容物进行加工修饰，再将其包装成囊泡用于分泌或运送到其他细胞器。
7. Cytoskeleton: The Internal Framework | 细胞骨架：内部支架
The cytoskeleton is a network of protein filaments that extends throughout the cytoplasm of both animal and plant cells. It provides structural support, maintains cell shape, and facilitates intracellular transport and cell movement.
细胞骨架是一个贯穿于细胞质中的蛋白质丝状网络，存在于动物细胞和植物细胞中。它提供结构支撑，维持细胞形态，并促进细胞内运输和细胞运动。
Three main types of filaments form the cytoskeleton: microfilaments (actin), microtubules (tubulin), and intermediate filaments. Each has distinct functions in maintaining cell structure and enabling movement.
细胞骨架由三种主要纤维构成：微丝（肌动蛋白）、微管（微管蛋白）和中间纤维。每一种在维持细胞结构和实现运动中都有独特的功能。
Microtubules are essential for the movement of chromosomes during cell division — both animal and plant cells form a spindle apparatus made of microtubules to separate sister chromatids.
微管在有丝分裂期间对染色体的移动至关重要——动物细胞和植物细胞都会形成由微管构成的纺锤体，以分离姐妹染色单体。
In animal cells, microfilaments enable cell movement and division (cytokinesis via a contractile ring), while in plant cells the cytoskeleton guides the positioning of the cell plate during cytokinesis.
在动物细胞中，微丝驱动细胞移动和分裂（通过收缩环完成胞质分裂）；在植物细胞中，细胞骨架则引导分裂过程中细胞板的定位。
8. Enzymes: Shared Metabolic Machinery | 酶：共用的代谢机器
Both animal and plant cells depend on enzymes — biological catalysts that accelerate chemical reactions without being consumed. The principles of enzyme action, including the induced-fit model and the effects of temperature and pH, apply equally in both cell types.
动物细胞和植物细胞都依赖酶——这种生物催化剂能在不被消耗的情况下加速化学反应。酶的作用原理，包括诱导契合模型以及温度和pH值的影响，在两类细胞中是同样适用的。
Enzymes in both cell types have an active site with a specific three-dimensional shape that determines substrate specificity. This is a universal feature of enzyme catalysis across all living organisms.
两类细胞中的酶都具有特定三维形状的活性位点，这决定了底物的特异性。这是所有生物体中酶催化的普遍特征。
Many enzymes are common to both cell types, including those of glycolysis, the Krebs cycle, and DNA replication. This similarity underscores the shared ancestry of all eukaryotes.
许多酶是两类细胞共有的，包括糖酵解途径、三羧酸循环和DNA复制相关的酶。这种相似性强调了所有真核生物的共同祖先关系。
Factors affecting enzyme activity — temperature, pH, substrate concentration, and enzyme concentration — affect animal and plant enzymes in the same fundamental ways, although the optimal values may differ between species.
影响酶活性的因素——温度、pH、底物浓度和酶浓度——对动物酶和植物酶有着相同的影响规律，尽管不同物种的最适值可能有所差异。
9. Genetic Material: DNA and Chromosomes | 遗传物质：DNA与染色体
Animal and plant cells store their genetic information in the form of DNA, organised into chromosomes within the nucleus. The structure of DNA — a double helix composed of nucleotides — is identical in both kingdoms, as is the process of DNA replication.
动物细胞和植物细胞都以DNA形式存储遗传信息，并将DNA组织为细胞核中的染色体。DNA的结构——由核苷酸组成的双螺旋——在两个界中完全相同，DNA复制的过程也相同。
DNA is a polymer of nucleotides, each consisting of a deoxyribose sugar, a phosphate group, and one of four nitrogenous bases (A, T, G, C). This universal code is shared by all cellular life.
DNA是核苷酸的多聚体，每个核苷酸由脱氧核糖、一个磷酸基团和四种含氮碱基（A、T、G、C）中的一种组成。这一通用密码由所有细胞生物共享。
Gene expression, the process by which DNA is transcribed into mRNA and translated into protein, operates on the same principles in animal and plant cells. The genetic code is universal — the same codons specify the same amino acids in all organisms.
基因表达——DNA转录为mRNA再翻译为蛋白质的过程——在动物细胞和植物细胞中遵循相同的原则。遗传密码是通用的——在所有生物中，相同的密码子指定相同的氨基酸。
DNA replication occurs in the S phase of the cell cycle in both animal and plant cells, ensuring that each daughter cell receives a complete set of genetic information.
DNA复制在动物和植物细胞的细胞周期S期进行，确保每个子细胞获得一套完整的遗传信息。
10. Common Features at a Glance | 共同特征一览表
The table below summarizes the key structural and functional features shared by animal and plant cells, providing a quick revision reference for examinations.
下表总结了动物细胞与植物细胞共享的主要结构和功能特征，为考试复习提供快速参考。
| Feature 特征 | Animal Cells 动物细胞 | Plant Cells 植物细胞 |
| Plasma membrane 细胞膜 | Present 有 | Present 有 |
| Cytoplasm 细胞质 | Present 有 | Present 有 |
| Nucleus 细胞核 | Present 有 | Present 有 |
| Ribosomes 核糖体 | Present 有 | Present 有 |
| Mitochondria 线粒体 | Present 有 | Present 有 |
| ER and Golgi 内质网与高尔基体 | Present 有 | Present 有 |
| Cytoskeleton 细胞骨架 | Present 有 | Present 有 |
| Enzymes 酶 | Present 有 | Present 有 |
| DNA as genetic material DNA为遗传物质 | Present 有 | Present 有 |
11. Examination Tips | 考试提示
When answering questions about the shared features of animal and plant cells, candidates should focus on the functional significance of each structure rather than merely listing names. Examiners expect precise terminology and an appreciation of how these features contribute to cell survival.
回答有关动物细胞与植物细胞共同特征的问题时，考生应聚焦于每个结构的功能意义，而不仅仅是罗列名称。考官期望考生使用精准的术语，并能理解这些特征如何为细胞的生存做出贡献。
Always distinguish between features shared by both cell types and those that are unique to one type. For example, the cell wall, chloroplasts, and the large central vacuole are found only in plant cells, while centrioles are typically associated with animal cells.
始终区分两类细胞共有的特征与某一类细胞独有的特征。例如，细胞壁、叶绿体和大中央液泡仅存在于植物细胞中，而中心粒通常与动物细胞相关联。
Use correct technical terms: 'nuclear envelope' rather than 'nuclear membrane', 'cilia' rather than 'hairs', and describe the membrane as 'selectively permeable' rather than 'partially permeable' when a precise definition is required.
使用正确的专业术语：说“核膜”而不是“核被膜”，说“纤毛”而不是“毛发”，在需要精确定义时称细胞膜为“选择性通透”而不是“部分通透”。
When comparing diagrammatically, draw both cells to the same scale whenever possible, and label the shared features clearly. In CIE examinations, labelled diagrams of organelles are frequently tested.
在画图比较时，尽可能按同一比例绘制两种细胞，并清楚标注共同特征。在CIE考试中，标注细胞器图谱是经常考察的内容。
Published by TutorHao | Biology 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