Isolate bacteria
1 The bacteria cell 2 Elementary structure 3 Special structure
4 Bacterial growth and reproduction 5 Aseptic technique 6 Gram stains
7 Other staining techniques 8 media
9 Isolate bacteria from mixed populations
1 The bacteria cell
A． Size of bacteria
Bacteria is very small, its measure unit is micrometer (μm). To see bacteria, we must use microscope but not naked eyes. B．Shape of bacteria
There are three basic types of bacteria
Coccus(球菌): diplococcus（双球菌）; streptococcus（链球菌）; staphylococcus（葡萄球菌）; tetrads（四联球菌）; sarcina（八叠球菌）
Bacillus（杆菌）: streptobacillus（链杆菌）; coccobacillus（球杆菌）; mycobacterium（分支杆菌）; bifidobacterium（双歧杆菌）
Spiral（螺旋形的） bacterium: vibrio（弧菌）; spirillum（螺旋菌）; helicobacterium
（螺杆菌）
C．Structure of bacteria cell
Bacterial structure Elementary structure 1) Cell wall 2) Cell membrane 3) Cytoplasm（细胞质） 4) Nucleoid（类核） Special structure 5) Capsule 6) Flagellum(flagella)7) Pilus(pili) 8) spore
2 Elementary structure
2.1 Cell wall
According to the dye result, bacterium can be divided into two categories: Gram-positive bacteria(G+) and Gram-negative bacteria(G-).
医学微生物课件chapter3 Isolate bacteria
