Micro: Ch. 2 Quiz

Who was the first to describe "cells" in dead cork tissue? Hans Janssen Zaccharias Janssen Antonie van Leeuwenhoek Robert Hooke

Hooke

Which of the following statements is CORRECT about scanning electron microscopes? Thin segments must be used. Images of surface structures are produced. Glass lenses are used. The sample is placed in a vacuum. Stains can be applied to improve contrast.

Images of surface structures are produced.

What mordant is used in Gram staining? crystal violet safranin acid-alcohol iodine

Iodine

Why does immersion oil improve resolution? It allows light to travel at a uniform speed on its way to the lens. It decreases the working distance. It increases the numerical aperture. It increases numerical aperture and maintains a uniform light speed. It increases the angle of refraction of the light

It increases numerical aperture and maintains a uniform light speed

Who is the probable inventor of the compound microscope? Girolamo Fracastoro Zaccharias Janssen Antonie van Leeuwenhoek Robert Hooke

Janssen

Why are modern light microscopes better than the ones Leeuwenhoek used? Modern microscopes have a fivefold better resolution. Modern microscopes are compound instead of simple. Modern microscopes have lenses with smaller numerical apertures. Modern lenses are made of prisms. Modern microscopes are compound and have fivefold better resolution.

Modern microscopes are compound and have a fivefold better resolution

What is one difference between specimen preparation for a transmission electron microscope (TEM) and preparation for a scanning electron microscope (SEM)? Only the TEM specimen requires sputter coating. Only the SEM specimen requires sputter-coating. Only the TEM specimen must be dehydrated. Only the SEM specimen must be dehydrated.

Only the SEM specimen requires sputter-coating.

Which type of microscope is especially useful for viewing thick structures such as biofilms? a transmission electron microscope a scanning electron microscopes a phase-contrast microscope a confocal scanning laser microscope an atomic force microscope

a confocal scanning laser microscope

Which would be the best choice for viewing internal structures of a living protist such as a Paramecium? a brightfield microscope with a stain a brightfield microscope without a stain a darkfield microscope a transmission electron microscope

a darkfield microscope

What type of microscope uses an annular stop? a transmission electron microscope a scanning electron microscope a brightfield microscope a darkfield microscope a phase-contrast microscope

a phase-contrast microscope

Acidic dyes work best in low-pH environments. are negatively charged. are used for staining negatively charged molecular structures. are lipid soluble. are negatively charged and work best at low pH.

are negatively charged and work best at low pH

A structure that appears in a transmission electron micrograph but is not actually present in the specimen is known as a(n) antigen. biofilm. artifact. refraction. mordant.

artifact

Lasers are used to generate the images produced by ________ microscopes. fluorescent confocal phase-contrast atomic force both confocal and atomic force

atomic force

Which of the following microscopes produces the highest resolution images? dark-field differential interference scanning electron fluorescent atomic force

atomic force

The acid-fast stain is used to stain bacteria with waxy cell walls. bacteria lacking cell walls. living bacteria. endospores. bacteria with capsules.

bacteria with waxy cell walls

Heat is used to drive the stain into cells in the ________ staining procedure(s). endospore stain acid-fast stain capsule stain Gram stain both acid-fast and endospore stains

both acid-fast and endospore stains

Safranin dye is used as the counterstain in ________ stain(s). the Gram the endospore the acid-fast the flagellar both the Gram and the endospore

both gram stain and endospore

Which of the following are magnifying lenses? objectives oculars condensers dark-field stops both objectives and the oculars

both objectives and the oculars

The Gram stain works because of differences in the ________ of bacteria. genetic characteristics cell walls cell membranes antigens capsules

cell walls

The light path illustrated in the figure represents a ________ microscope. bright-field dark-field phase contrast fluorescence differential interference contrast

dark field

You are shown a micrograph from a light microscope in which the specimens appear bright compared to the background. The micrograph is probably from a(n) ________ microscope. dark-field phase-contrast Nomarski bright-field atomic force

dark field

What type of microscope uses a cone of light so that light only hits the specimen indirectly, producing a darker image on a brighter background? a transmission electron microscope a scanning electron microscope a brightfield microscope a darkfield microscope a phase-contrast microscope

darkfield microscope

A virologist wants to observe the surface features of virus particles she is studying. Which of the following microscopes would NOT be useful for her observations? differential interference contrast scanning tunneling scanning electron transmission electron atomic force

differential interference contrast

The light source in a ________ microscope is ultraviolet (UV) light. phase-contrast dark-field fluorescent Nomarski bright-field

fluorescent

You place a specimen under the microscope and notice that parts of the specimen begin to emit light immediately. These materials can be described as _____________. fluorescent phosphorescent transparent opaque

fluorescent

Which of the following has the highest energy? light with a long wavelength light with an intermediate wavelength light with a short wavelength It is impossible to tell from the information given.

light with a short wavelength

A measurement of a microbe is reported as 1 × 10-6 m, also known as centimeters (cm). millimeters (mm). micrometers (m). nanometers (nm). yards.

micrometers (μm).

In the Gram stain procedure, iodine serves as a counterstain. decolorizing agent. mordant. primary stain. fixative.

mordant

The ability of a lens to gather light is referred to as its resolution. numerical aperture. refraction. contrast. magnification.

numerical aperture

The part(s) of the microscope indicated by the arrows is/are the oculars. body. objectives. condenser lens. diaphragm.

objectives

Unstained cells that lack pigment are best observed on the ________ microscope. bright-field phase-contrast scanning electron scanning tunneling transmission electron

phase contrast

Bacteria and many other microbes do NOT ________ and therefore do NOT fit Linnaeus' definition of species. reproduce sexually have nuclei exchange genetic material have cytoplasmic membranes reproduce asexually

reproduce sexually

This image was most likely produced by a ________ microscope. scanning electron confocal bright-field transmission electron dark-field

scanning electron

Which type of microscope would be the best choice for viewing very small surface structures of a cell? a transmission electron microscope a scanning electron microscope a brightfield microscope a darkfield microscope a phase-contrast microscope

scanning electron microscope

A thin film of microbes on a slide is fixation. a smear. a Gram reaction. a biopsy. agglutination.

smear

High resolution images of the internal structures of microbial cells are obtained using ________ microscopes. atomic force scanning tunneling transmission electron confocal scanning electron

transmission electron