Question

1. describe the two different ways that bacteria can be classified.

Explanation:

One way is by their shape: coccus (spherical), bacillus (rod - shaped), spirillum (spiral). Another way is by their cell wall structure (Gram - positive or Gram - negative) based on Gram staining, or by their oxygen requirements (aerobic, anaerobic, facultative anaerobic), or by their nutritional mode (autotrophic, heterotrophic).

Answer:

1. By shape: Coccus (spherical), Bacillus (rod - shaped), Spirillum (spiral).
2. By cell wall structure (Gram - staining): Gram - positive (thick peptidoglycan layer, retain crystal violet stain) and Gram - negative (thin peptidoglycan layer, do not retain crystal violet stain, take up safranin counterstain) (or by oxygen requirements: aerobic (need oxygen), anaerobic (cannot tolerate oxygen), facultative anaerobic (can live with or without oxygen); or by nutritional mode: autotrophic (make own food, e.g., photosynthetic or chemosynthetic) and heterotrophic (obtain food from other sources)).