37.2
The biological world is organized as a hierarchy, the largest of which is the biosphere, containing all of life on Earth.
Within the biosphere are many different ecosystems like this forest. Ecosystems consist of many communities that are made up of populations of different species, sharing resources and interacting with one another and the surrounding environment.
At the organism level, organ systems within the body work together to ensure survival and reproduction.
An organ is made of different tissues. For example, the largest organ, the skin, contains epithelial tissue, connective tissue, nervous tissue, and muscle tissue. Each tissue includes millions of cells, the basic structural and functional unit of life.
Inside cells are organelles, functional compartments like mitochondria, endoplasmic reticulum, and golgi apparatus, which build, break down, and transport many different molecules like proteins.
These interconnected levels help structure the biological world.
生物组织是对生物结构的分类,从最底层的原子到地球生物圈。层次结构的每一层都表示在前一层基础上增加的复杂性。
最基本的水平包括原子、分子和生物分子。原子是普通物质的最小单位,由原子核和电子组成。分子由两个或多个由化学键(通常是共价键、离子键或金属键)结合在一起…