亚生物学领域的证据有助于划分物种和更高级的分类单位，然而物种最初依据形态学特征进行分类的，今天生物学家大体上使用孤立多产的群体作为标准。

Taxonomy reveals a great deal about the evolutionary relationships among organisms. A clade is a taxonomic unit whose members are derived from a common ancestor. 分类学揭示了物种间进化的大量关系。进化枝中的成员来自一个共同的祖先。 The Five Kingdoms

A phylogenetic tree is a graphic representation of evolutionary relationships. Your text uses a common five-kingdom arrangement: organisms are grouped into the kingdoms Monera, Protista, Fungi, Plantae, and Animalia. Although this system is a convenient organizational tool, the kingdoms are probably no true clades.

进化系统树是进化关系的图解表现。教材中使用一个通用的5界：？，？，真菌，植物，动物。尽管这个系统是一个便利的组织工具，5界划分可能不是正确的进化枝。 课后作业：第一篇阅读材料 答案：1B,2A,3B,4C,5A,6C

Glossary

Big Bang 大爆炸

An explosion producing a pressure oscillation of the order of a millibar or more at a distant point on the Earth. e.g., the eruption of Krakatoa in 1883. Large nuclear fusion explosions are comparable. crust 地壳

The crust of the Earth is the outer shell of the Earth, defined by its composition and the properties of some seismic waves. mantle 地幔

The part of the interior of the Earth between the crust and the core.

core 核心

The core of the Earth is that part lying below the mantle.

coacervate 团聚体，凝聚层

A collection of organic macromolecules surrounded by water molecules that are aligned to fon-n a sphere. liposome 脂质体

A vesicle formed by the homogenization (emulsification) of phospholipids in dilute salt solutions. Liposomes are the prototypes of membrane-bound biologic structures. ozone layer 臭氧层

A layer of the atmosphere, about 20 to 50 km above the surface, which contains ozone produced by ultraviolet radiation. proteinoid 类蛋白[质]

A proteinlike structure of branched amino acid chains that is the basic structure of a microsphere.

continental drift 大陆漂移

The theory that the present continents result from the break-up of a larger continent and have moved independently to their present positions.

binomial system of nomenclature双名法

Uses two Latin names, genus and species, for each type of organism. genus 属

(plural, genera) A unit used in the classification of plants and animals. A genus consists of a number of closely related species, and members of the same genus often have a number of obvious characteristics in common by which they can clearly be seen to be related.

species 物种

A unit used in the classification of plants and animals. Ideally a species is defined as a group of organisms that interbreed with each other to produce fertile offspring.

family 科

A unit used in the classification of plants and animals. A family consists of a number of closely related or similar genera or occasionally of only one genus. Family names end in -aceae or -ae in botany and in -ideae in zoology. order 目

A unit used in the classification of plants and animals. An order consists of a number of similar or closely related families or only on family. Names of orders end typically in -ales in plants and in -a in animals. class 纲

A group used in the classification of living organisms. A class consists of a number of similar or closely related orders or occasionally of only one order. Classes are usually large and easily recognized groups. division 门

A unite used in the classification of plants. A division consists of a number of classes, or occasionally of only on class, with certain important characteristics in common. phylum 门 (复数 phyla)

A unit used in the classification of animals. A phylum consists of a number of classes, or occasionally of only one class, with certain important characteristics in common, implying that all members are descended from a common ancestor. kingdom 界

In biology, a major category into which living material is classified.

taxon 分类单位，分类群 (复数 taxa )

A unit of classification of any rank in the hierarchical scale. taxonomy 分类学

The study of the theory, procedure, and rules of classification of organisms according to the Similarities and differences between them clade 进化枝，分化单位

In a cladistic classification, organisms are placed into taxonomic groups called clades when they share characteristics that are thought to indicate common ancestry.

Fungi: The Great Decomposers

Characteristics of Fungi

The approximately 175,000 species of fungi include some of the simplest multicellular organisms. Fungi have a variety of lifestyles. They may be saprobes that decompose dead organic matter; they may be parasites which obtain nutrients from living hosts; or they may live in symbiotic relationships with algae or with the roots of higher plants. In spite of these variations, however, all fungi carry out extracellular digestion: they secrete enzymes that digest organic matter, and then they absorb the resulting nutrients.

包括最简单的多细胞生物在内，真菌大概有175，000种。真菌有多种生命形式。他们可能是分解无生命的腐生菌；也可能是寄生菌；或者与藻类共生，或者与高等植物共生。不管如何变化，所有真菌都是细胞外消化。他们分泌酶消化有机物，然后吸收有效的营养物质。

Most fungi have the same basic body structure consisting of a main body or thallus composed of filaments called hyphae. In most species the walls of hyphal cells contain chitin. Hyphae in certain species may become specialized to form rhizoids, which serve as rootlike anchors, or they may become the feeding structures known as haustoria. Finally, hyphae may or may not be septate-having cross walls that segregate independent cells, each with at least one nucleus. Lower fungi are coenocytic; that is, they are one mass of cytoplasm that contains multiple nuclei. 大多数真菌有同样的基本结构，即由菌丝组成的菌体。大多数真菌的细胞壁含有明角质。某些种类的菌丝可能特化形成假