2.1.1 The cell is the fundamental unit of life

Cell theory:

  1. All organisms are made up of cells.
  2. The cell is the fundamental unit of life.
  3. Cell came from preexisting cells.

Cells vary in shape.

SEMs 扫描式电子显微镜 Scanning 展示外部结构

TEMs 透射式电子显微镜 Transmission 展示内部结构

Cell fractionation 细胞分离: Differential centrifugation 差速离心

2.1.2 Procaryotes and Eucaryotes differ in internal organization

Basic features of all cells:

  1. Plasma membrane
  2. Cytosol
  3. Ribosome
  4. Genetic material

Differences between P. & E. cells:

Prokaryotes Eukaryotes
no nucleus DNA in nucleus
DNA in an unbounded region called Nucleoid(拟核) membrane bounded organisms
no membrane bounded organisms cytoplasm in the region between the plasma membrane & nucleus

Size: P. cell < E. cell