📚 Organisms: KS3 CIE Year 7 Scheme of Work | 生物体：KS3 CIE 七年级教学计划
This revision guide covers the Year 7 Organisms topic for the Cambridge Lower Secondary (CIE) science curriculum. You will learn what makes something living, how cells build organisms, how to use a microscope, and how scientists sort and identify living things.
本复习指南涵盖剑桥初中（CIE）科学课程七年级"生物体"主题。你将学习是什么让事物具有生命，细胞如何构建生物体，如何使用显微镜，以及科学家如何对生物进行分类和识别。
1. What is an Organism? | 什么是生物体？
An organism is a living thing that can carry out all seven life processes. This means it can move, respire, sense changes, grow, reproduce, excrete waste, and take in nutrition.
生物体是能够执行所有七大生命过程的物体。这意味着它能运动、呼吸、感知变化、生长、繁殖、排泄废物并摄取营养。
Organisms range from single-celled bacteria to complex multicellular plants and animals. Examples include humans, oak trees, mushrooms, and even microscopic amoebae.
生物体从单细胞细菌到复杂的多细胞植物和动物各不相同。例子包括人类、橡树、蘑菇，甚至微小的变形虫。
2. The Seven Life Processes (MRS GREN) | 七大生命过程（MRS GREN）
To remember the seven life processes, use the acronym MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion, Nutrition.
要记住七大生命过程，可以使用缩写 MRS GREN：运动、呼吸、应激性、生长、繁殖、排泄、营养。
| Life process | What it means | 中文含义 |
|---|---|---|
| Movement | Changing position or moving parts of the body | 运动 - 改变位置或移动身体部位 |
| Respiration | Releasing energy from food inside cells | 呼吸 - 在细胞内从食物中释放能量 |
| Sensitivity | Detecting and responding to changes in the environment | 应激性 - 检测并响应环境变化 |
| Growth | Increasing in size and number of cells | 生长 - 大小和细胞数量增加 |
| Reproduction | Producing new organisms | 繁殖 - 产生新生物体 |
| Excretion | Removing waste products made by the body | 排泄 - 排出身体产生的废物 |
| Nutrition | Taking in and using food for energy and growth | 营养 - 摄取并利用食物获取能量和生长 |
Not all organisms show movement in an obvious way. For example, plants grow towards light, which is a slower type of movement.
并非所有生物都以明显的方式运动。例如，植物向光生长就是一种较慢的运动。
3. Cells: The Building Blocks of Life | 细胞：生命的基本单位
Cells are the basic units of life. Every organism is made of at least one cell, and most cells are too small to see without a microscope.
细胞是生命的基本单位。每个生物体至少由一个细胞构成，大多数细胞太小，没有显微镜无法看到。
The cell theory states that all living things are made of cells, and new cells come from existing cells.
细胞学说指出，所有生物都由细胞组成，新细胞来自已有细胞。
Some organisms, such as bacteria and amoebae, are unicellular. Others, like humans and trees, are multicellular.
有些生物如细菌和变形虫是单细胞的。其他如人类和树木是多细胞的。
4. Animal and Plant Cells | 动物细胞与植物细胞
Animal cells usually contain a nucleus, cytoplasm, cell membrane, and mitochondria. The nucleus controls the cell and contains genetic material.
动物细胞通常包含细胞核、细胞质、细胞膜和线粒体。细胞核控制细胞并含有遗传物质。
Plant cells have the same basic parts plus a rigid cell wall, chloroplasts for photosynthesis, and a large permanent vacuole filled with cell sap.
植物细胞除了相同的基本部分外，还有坚硬的细胞壁、进行光合作用的叶绿体，以及充满细胞液的大液泡。
| Cell part | Function | 中文功能 |
|---|---|---|
| Nucleus | Controls cell activities and contains DNA | 控制细胞活动并含有 DNA |
| Cytoplasm | Site of chemical reactions | 化学反应的场所 |
| Cell membrane | Controls what enters and leaves the cell | 控制物质进出细胞 |
| Cell wall | Provides support in plant cells | 为植物细胞提供支撑 |
| Chloroplasts | Absorb light for photosynthesis | 吸收光进行光合作用 |
| Vacuole | Stores cell sap and helps maintain rigidity | 储存细胞液并帮助保持硬度 |
| Mitochondria | Release energy during respiration | 在呼吸过程中释放能量 |
In Year 7, you should be able to label these parts on a simple diagram and describe their functions.
在七年级，你应该能够在简单示意图上标出这些部分并描述其功能。
5. Levels of Organisation | 组织层次
In multicellular organisms, cells are organised into larger structures. A group of similar cells working together forms a tissue.
在多细胞生物中，细胞组织成更大的结构。一组相似的细胞协同工作形成组织。
Different tissues working together form an organ, such as the heart or leaf. Organs that work together form an organ system.
不同组织协同工作形成器官，如心脏或叶。协同工作的器官形成器官系统。
- Cells (e.g. muscle cells) - 细胞（如肌细胞）
- Tissues (e.g. muscle tissue) - 组织（如肌肉组织）
- Organs (e.g. stomach) - 器官（如胃）
- Organ systems (e.g. digestive system) - 器官系统（如消化系统）
- Organism (e.g. human) - 生物体（如人类）
Specialised cells, such as nerve cells, sperm cells, and root hair cells, have adaptations that help them carry out their specific jobs.
特化细胞如神经细胞、精子和根毛细胞具有帮助它们完成特定功能的适应性。
6. Using a Microscope | 使用显微镜
A light microscope is used to magnify cells so we can see their details. It has an eyepiece lens and objective lenses.
光学显微镜用于放大细胞，以便观察其细节。它有目镜和物镜。
To calculate total magnification, multiply the eyepiece magnification by the objective lens magnification.
计算总放大倍数时，将目镜放大倍数乘以物镜放大倍数。
Total magnification = Eyepiece magnification × Objective lens magnification
Always start with the lowest power objective lens, use the coarse focus first, and then the fine focus to get a sharp image.
始终从最低倍物镜开始，先使用粗调焦，再使用细调焦以获得清晰图像。
- Eyepiece lens - 目镜
- Objective lenses - 物镜
- Stage - 载物台
- Mirror or light source - 反光镜或光源
- Coarse focus - 粗调焦
- Fine focus - 细调焦
Published by TutorHao | KS3 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