Question

Which types of microscope(s) would be used to examine the following specimens? Photosynthetic

bacteria, spirochetes, GFP-labeled microorganisms, unstained microbes, and pond scum; please explain

your answers

Answer 1

Photosynthetic bacteria: The compound light microscope because it combines light and power of lens to enlarge the view. Most bacteria are 0.2 um in diameter and 2-8 um in length with a number of shapes, ranging from spheres to rods and spirals, single bacteria are transparent in appearance therefore you can phase contrast optics.

Spirochetes: Dark Field Microscope because this microscope contains a special condenser that scatters light and causes it to reflect off the specimen at an angle. A light object is seen on a dark background.

GFP-labeled microorganisms :  Epifluorescence and laser confocal microscopy​​​​​​​ because it uses ultraviolet light as its light source. When ultraviolet light hits an object, it excites the electrons of the object, and they give off light in various shades of color. Using fluorescent‐antibody technique helps identify unknown microorganisms.​​​​​

Unstained microbes: Electron microscope because it produces 3 dimensional images

Pond scum: Light Microscopy ​​​​​​​because Typically, pond water will contain a variety of microorganisms with a drop of the water carrying thousands of these single celled organisms.