Who Am I? Identifying Living Things | 我是谁？识别生物

📚 Who Am I? Identifying Living Things | 我是谁？识别生物

In KS3 Science, the question “Who am I?” is a fun way to check your understanding of living things, cells and classification. This article will help you revise the key ideas by giving you clear clues, definitions and examples. You will learn how to identify an organism from its features, how cells are organised, and how scientists group living things.

在 KS3 科学课程中，”我是谁？”这个问题是一种检验你对生物、细胞和分类理解的有趣方式。本文将通过清晰的线索、定义和例子帮助你复习关键概念。你将学会如何根据特征识别生物、细胞如何组成，以及科学家如何对生物进行分类。

1. Characteristics of Living Things | 生物的共同特征

All living things carry out seven life processes. A common way to remember them is the acronym MRS GREN: Movement, Respiration, Sensitivity, Growth, Reproduction, Excretion and Nutrition. If an organism shows all seven processes, it is considered alive.

所有生物都会进行七项生命活动。一个常用的记忆方法是首字母缩略词 MRS GREN：运动（Movement）、呼吸（Respiration）、感应（Sensitivity）、生长（Growth）、生殖（Reproduction）、排泄（Excretion）和营养（Nutrition）。如果一个生物表现出全部七项活动，它就被认为是活的。

For example, a plant moves slowly by growing towards light, respires to release energy, senses gravity, grows, reproduces by seeds, excretes oxygen as a waste product, and makes its own food by photosynthesis.

例如，植物通过向光生长缓慢移动，通过呼吸释放能量，感知重力，生长，通过种子繁殖，将氧气作为废物排出，并通过光合作用制造自己的食物。

2. Cells: The Building Blocks | 细胞：生命的基本单位

Cells are the smallest unit of life. Some organisms are made of just one cell (unicellular), such as bacteria and amoeba. Others, like humans and oak trees, are multicellular, meaning they are made of many specialised cells that work together.

细胞是生命的最小单位。有些生物只由一个细胞构成（单细胞生物），例如细菌和变形虫。其他生物，如人类和橡树，是多细胞生物，这意味着它们由许多特化的细胞共同工作组成。

The idea of cells was first described by Robert Hooke in 1665 when he observed thin slices of cork under a microscope. He named the tiny compartments ‘cells’.

细胞的概念最早由罗伯特·胡克在 1665 年描述，当时他在显微镜下观察软木薄片，并把那些微小的隔室命名为 “细胞”。

3. Animal and Plant Cells | 动物细胞与植物细胞

Both animal and plant cells contain a cell membrane, cytoplasm, nucleus, mitochondria and ribosomes. The nucleus controls the cell’s activities and contains genetic material. Mitochondria release energy through respiration.

动物细胞和植物细胞都含有细胞膜、细胞质、细胞核、线粒体和核糖体。细胞核控制细胞的活动并含有遗传物质。线粒体通过呼吸作用释放能量。

Plant cells have three extra structures: a cell wall made of cellulose for support, chloroplasts for photosynthesis, and a large permanent vacuole containing cell sap.

植物细胞有三种额外的结构：由纤维素组成的细胞壁起支撑作用，叶绿体进行光合作用，以及一个含有细胞液的大型永久液泡。

The table above summarises the key differences you need to remember for the exam.

上表总结了你需要在考试中记住的关键差异。

4. Using a Microscope | 使用显微镜

To see cells clearly, you use a light microscope. A typical school microscope has an eyepiece lens (usually ×10) and three objective lenses (for example ×4, ×10, ×40).

为了清楚地观察细胞，你需要使用光学显微镜。学校常用的显微镜有一个目镜（通常为 ×10）和三个物镜（例如 ×4、×10、×40）。

The total magnification is calculated by multiplying the two lens powers:

总放大倍数的计算方法是两个镜头倍数的乘积：

Total magnification = eyepiece magnification × objective magnification

For example, if the eyepiece is ×10 and the objective is ×40, the total magnification is ×400.

例如，如果目镜为 ×10，物镜为 ×40，则总放大倍数为 ×400。

5. Classification of Living Things | 生物的分类

Classification means sorting living things into groups based on similarities. The main levels of classification,

Published by TutorHao | KS3 Revision Series | aleveler.com

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