Principles of microbiology

Part – I
a) Briefly explain the principles of microscopy
b) What is the difference between magnification and resolution
c) Compare and contrast bright-field and dark-field microscopes
d) Explain how phase-contrast and fluorescence microscopes work.
Part – II
a) Explain the importance of staining techniques in microbiology
b) Explain the principle and describe the procedure (giving rationale for each step) of:
i. Gram stain
ii. Acid-fast stain
Part – III
Explain in details any five (physical or chemical) ways of controlling microbial growth in the food industry.