The Characteristics of Living Things

生物体的特征

Biology as the study of living things is a vast and fascinating field. To get a starting point in the study of biology, it is perhaps worthwhile to try to define what you mean by "life". Audesirk and Audesirk give a list of basic characteristics of living things. Karp approaches the same ideas in terms of the properties of living cells.

生物学是研究生命现象的广阔而迷人的领域。要开始学习生物学，或许值得尝试定义你对‘生命’一词的理解。Audesirk和Audesirk列出了一些生物的基本特征。Karp则从活细胞的性质来阐述相同的观点。

Yockey has a very concise characterization of life: "The existence of a genome and the genetic code divides living organisms from nonliving matter."

Yockey 对生命的描述非常简洁：‘存在基因组和遗传密码将生物体与非生命物质区分开来。’

Classification of Organisms

生物分类

The word "organism" may be used to describe one individual living system. It can be thought of as the smallest unit of that kind of life that possesses all the characteristics of life. Audesirk & Audesirk supply the following table of characteristics used to classify organisms.

‘生物’这个词可以用来描述一个个体生命系统。它可以被看作是具有所有生命特征的最小生命单位。Audesirk与Audesirk提供了以下用于分类生物的特征表。

Domain 域	Kingdom 王国	Cell Type 细胞类型	Cell Number 电池数量	Major Mode of Nutrition 主要营养模式
Bacteria 细菌	??	Prokaryotic 原核	Unicellular 单细胞的	Absorption, photosynthesis 吸收，光合作用
Archaea 古菌	??	Prokaryotic 原核	Unicellular 单细胞的	Absorption 吸收
Eukarya 真核生物	Protista 原生生物	Eukaryotic 真核	Unicellular 单细胞的	Absorption, ingestion, or photosynthesis 吸收、摄入或光合作用
Eukarya 真核生物	Fungi 真菌	Eukaryotic 真核	Multicellular 多细胞的	Absorption 吸收
Eukarya 真核生物	Plantae 植物界	Eukaryotic 真核	Multicellular 多细胞的	Photosynthesis 光合作用
Eukarya 真核生物	Animalia 动物界	Eukaryotic 真核	Multicellular 多细胞的	Ingestion 摄入

Those organisms that make use of photosynthesis manufacture their food by capturing energy from sunlight and constructing energy-rich molecules such as sugars and fats. These organisms are called "autotrophs", meaning "self-feeders". Other organisms must obtain their energy-rich molecules from other organisms and are called "heterotrophs" or "other-feeders".

那些利用光合作术的生物通过捕获阳光中的能量并构建能量丰富的分子如糖类和脂肪来制造食物。这类生物被称为“自养生物”，意为“自我养活”。其他生物则必须从其他生物获取能量丰富的分子，被称为“异养生物”或“他养生物”。