Micro Quiz 2

What is the most important tool for observing microorganisms?

• Telescope

• Microscope

• Binoculars

• Magnifying glass

Which type of light provides the best resolution in a light microscope?

• Red light

• Green light

• Blue light

• Yellow light

What can an electron microscope (EM) be used to observe?

• Intact cells

• Internal cell structure and details of cell surface

• Stars

• Planets

What is a characteristic of a compound light microscope?

• Uses a single lens

• Uses a lens of short focal length followed by a longer focal length lens

• Uses only natural light

• Uses a prism to form images

What is the magnification level of the eyepiece (ocular lens) typically used in microscopes?

• 5X

• 10X

• 15X

• 20X

What is the purpose of the eyepiece in a microscope?

• To hold the specimen

• To magnify the image

• To focus light on the specimen

• To adjust the magnification

What is the function of the field diaphragm in a microscope?

• To adjust the focus

• To control the amount of light

• To magnify the image

• To hold the specimen

What is a challenge when using a bright-field microscope to observe microorganisms?

• Microorganisms have distinctive phase contrast.

• Microorganisms are easy to see without staining.

• Microorganisms do not have distinctive phase contrast with the surrounding medium.

• Microorganisms are naturally colorful.

What color do Gram-positive cells appear after Gram staining?

• Pink to red

• Blue

• Purple

• Colorless

What happens to Gram-negative cells after the decolorization step in Gram staining?

• They remain purple.

• They become colorless.

• They turn blue.

• They become green.