Microscopy

Question 1

what is magnification?

Answer 1

apparent enlargement of a specimen

Question 2

What is resolution?

Answer 2

shortest distance between two objects can still be distinguished as two separate objects

Question 3

What some detail about light microscopy?

Answer 3

• modern light microscopes can get x2000 & x1000 is fairly standard
• limited ability to visualize bacterial components or distinguish between bacteria without doing something extra

Question 4

What some details about staining?

Answer 4

• Safranin and Crystal violet in the gram stain

- staining is related to cell wall thickness, will kill specimens

Question 5

What is Phase contrast microscopy?

Answer 5

• separates light going into specimen, creating more contrast between specimen and background
• good for observing smaller details such as motility

Question 6

What is fluorescence microscopy?

Answer 6

• fluorochromes that emit light of specific wavelengths when excited by light of different wavelength
• can be an external due, attached to a molecule such as an antibody or DNA probe
• can be engineered into genes and viewed in living cells
• good for internal cell structures?

Question 7

What is Electron Microscopy?

Answer 7

• scanning EM: to view exterior

- transmission EM: to view small internal structures smallest specimens

Question 8

Magnetostatic bacteria

Answer 8

• bacteria that will align with magnetic field (magnetosomes)

Question 9

Scanning probe microscopy

Answer 9

• “tip” can be a physical object or an electron cloud in scanning tunneling microscopy