Concept explainers
To review:
The bacterial features that can be studied by the following techniques of microscopy: light microscopy, fluorescence microscopy, scanning electron microscopy, transmission electron microscopy.
Introduction:
The human eye can resolve things that are up to 1 millimeter in size. In order to resolve the objects below this size, human eyes need equipment that has greater resolving power. Microscopes are equipment that are used to imagine the objects that cannot be resolved by the eyes.
There are various types of microscopes that are used for imaging the bacteria and other microscopic entities. All microscopes operate on the same principles of physics, refraction of light leading to magnification. The illumination and magnification in several microscopes can be obtained from the light while some use electron beams. The bacterial features that can be studied by the above-mentioned techniques of the microscopy are listed below:
1. Light microscopy: The shape of the bacteria can be revealed by using light microscopy. The bacteria that form the chain can also be detected using this technique. The cell wall of the Gram-positive and Gram-negative bacteria can also be examined under light microscopy.
2. Fluorescence microscopy: Fluorescent dyes are used in this technique. These dyes can bind up with the specific macromolecules present in a particular region of the cell. Thus, the specific position of the organelles can be revealed by this technique. This technique can also be used to trace various ongoing biological processes in the cell-like replication.
3. Scanning electron microscopy : A beam of electron is used in this technique in order to magnify the image. It can help in detecting the surface details of the bacteria. The composition of the external surface of the cell can be revealed by this technique.
4. Transmission electron microscopy: This technique is similar to the bright light microscope except for an electron source from a tungsten filament instead of a light source. It is used to reveal internal details of microorganisms like the presence of flagellum. The cell organelles can also be revealed by using this technique of microscopy.
Want to see the full answer?
Check out a sample textbook solutionChapter 2 Solutions
Microbiology: An Evolving Science (Fourth Edition)
- You are interested in studying the surface structure of an Archaea cell, what type of microscopy will you use? a) scanning electron microscopy b) phase-contrast microscopy c) transmission electron microscopy d) bright-field microscopyarrow_forwarda) Briefly describe the concept of and instrument configuration for confocal microscopy. b) How do confocal and conventional microscopy compare? c) What other microscopy techniques can provide super-resolution?arrow_forward11) You can increase the microscope ability to enlarge a specimen by: a) increasing the refractive index b) decreasing the refractive index c) decreasing d) increasing e) a & c12) The two tetrapeptides that form the cross linking between the peptidoglycan layers are linked by: a) phosphodiester bond b) pentapeptide c) a side chain tetrapeptide d) either bond e) b & d13) A large cluster (more than 8) of bacillus bacteria is called: a) coccus b) streptococcus c) staphylococcus d) octa bacillus e) none of the abovearrow_forward
- You wish to identify the presence of a specific protein inside the cell. What microscopy technique should you use? a) Transmission electron microscopy b) Light microscopy Oc) Scanning electron microscopy d) Fluorescent microscopy e) None of the abovearrow_forwardUsing bright-field microscopy to look at a slide prepared with a basic dye you observe cells with a clear inner compartment within the cell at 400X magnification. The cell is most likely a(n) A) prokaryote. B) bacterium. C) archaeon. D) eukaryote.arrow_forwardPlace the path of light (using the numbers) in the microscope in the proper order as the light travels from its source until it hits the researcher’s eye: 1) condenser 2) light source 3) nose- piece lens 4) ocular lens 5) slide a) 1, 2, 5, 4, 3 b) 1, 3, 4, 2, 5 c) 2, 1, 5, 3, 4 d) 3, 2, 1, 4, 5 e) 1, 3, 4, 2, 5arrow_forward
- Which of the following methods used to enumerate cells often requires specialized staining to observe nonpigmented bacteria? A) Spectrophotometry/turbidity B) Spread-plating C) Microscopy D) Spread-plating, turbidity, and microscopyarrow_forwardIf a microscope has a 40x objective lens in place and a 15x ocular lens, the total magnification of the microscope system under these conditions is _____. a) 600x b) 2.7x c) 55x d) 30xarrow_forward1-What is a compound light microscope? Please name its parts. 2- a:)What is magnification? b) Light microscopes magnify an object no more than ____________________. 3- a) What is resolution? b)What are the factors to increase light microscope resolution?arrow_forward
- What are the advantages of using super-resolution microscopyversus standard fluorescence microscopy?arrow_forwardWhich Two types of electron microscopy are in routine use in microbiology? Explainarrow_forwardWhat advantages do confocal and deconvolution microscopy provide in comparison to conventional fluorescence microscopy?arrow_forward